When calculating the determinant of a matrix, the answer is a single number rather than a matrix.

Answers

Answer 1

Answer:

Yes, one of the properties of determinants is that they are real numbers (including zero) not matrix. This if the entries of the matrix are real. Determinants can be both positive or negative numbers.

Step-by-step explanation:

Answer 2

The determinant of a matrix is a number

What is a Matrix?

In mathematics, a matrix is a rectangular array or table of numbers, symbols, or expressions, arranged in rows and columns, which is used to represent a mathematical object or a property of such an object

The determinant of inverse matrix can never be zero.

The determinant of an identity matrix is always 1.

The determinant of a zero matrix is always 0.

Given data ,

Let the matrix be represented as

[tex]A = \left[\begin{array}{ccc}a_{11} &a_{12} \\ a_{21} &a_{22} \\\end{array}\right][/tex]

Let the determinant of the matrix be d

Now , the determinant of the matrix A is calculated as

d = ( a₁₁ ) x ( a₂₂ ) - ( a₁₂ ) x ( a₂₁ )

So , the determinant will be a single number and will not be another matrix

The value of d will be scaling factor for the transformation of a matrix

Hence , the determinant of a matrix is a number

To learn more about matrix click :

https://brainly.com/question/13215296

#SPJ2


Related Questions

Use technology to find the​ P-value for the hypothesis test described below. The claim is that for 12 AM body​ temperatures, the mean is mu μ greater than > 98.6 98.6 degrees °F. The sample size is n equals = 9 9 and the test statistic is t equals = 2.132 2.132.

Answers

Answer:

P-value = 0.032794

Step-by-step explanation:

We are given the following information in the question:

Population mean, μ = 98.6 degrees

Sample size, n = 9

Alpha, α = 0.05

Test t-statistic = 2.132

The null and the alternate hypothesis :

[tex]H_{0}: \mu = 98.6\text{ degrees}\\H_A: \mu > 98.6\text{ degrees}[/tex]

We have to find the p-value for degree of freedom 8 and significance level 0.05

The calculated p-value is 0.032794

Average expenditure on different items such as food, clothes, fuel comes under ____. Select one: a. Descriptive statistics b. Inferential statistics c. Applied statistics d. Business statistics e. Industrial statistics

Answers

Answer:

Descriptive

Step-by-step explanation:

Statistics can be broadly classified into two main branches

i) Descriptive and ii) inferential

Descriptive statistics deal with values such as mean, standard deviation from the data.

Inferential statistics is used to predict unknown values from the observed values.

Applied statistics mainly analyses the data according to the needs of business or industries.

Hence the average expenditure on different items such as food, clothes, fuel comes under

Descriptive Statistics

Final answer:

Average expenditure on different items like food, clothes, and fuel falls under descriptive statistics, essential for summarizing trends in expenditure data. The correct option is a.

Explanation:

Descriptive statistics involve summarizing trends in data, such as calculating averages and standard deviations, making them suitable for analyzing average expenditures on items like food and clothes.

Inferential statistics are used to make inferences about populations based on sample data, aiming to find cause and effect relationships or correlations, which is essential when studying average expenditures across different categories.

Therefore, analyzing average expenditures on various items falls under the domain of descriptive statistics as it involves summarizing and interpreting trends in expenditure data.

A website advertises job openings on its website, but job seekers have to pay to access the list of job openings. The website recently completed a survey to estimate the number of days it takes to find a new job using its service. It took the last 30 customers an average of 60 days to find a job. Assume the population standard deviation is 10 days. Construct a 90% confidence interval of the population mean number of days it takes to find a job.

Answers

Answer:

The 90% confidence interval would be given by (57.006;62.994)  

Step-by-step explanation:

Previous concepts

The margin of error is the range of values below and above the sample statistic in a confidence interval.  

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".  

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".

[tex]\bar X=60[/tex] represent the sample mean  

[tex]\mu[/tex] population mean (variable of interest)  

[tex]\sigma=10[/tex] represent the population standard deviation  

n=30 represent the sample size  

Assuming the X follows a normal distribution  

[tex]X \sim N(\mu, \sigma=10)[/tex]

The sample mean [tex]\bar X[/tex] is distributed on this way:

[tex]\bar X \sim N(\mu, \frac{\sigma}{\sqrt{n}})[/tex]  

The confidence interval on this case is given by:

[tex]\bar X \pm z_{\alpha/2}\frac{\sigma}{\sqrt{n}}[/tex] (1)

The next step would be find the value of [tex]\z_{\alpha/2}[/tex], [tex]\alpha=1-0.90=0.1[/tex],[tex]\alpha/2 =0.05[/tex] and [tex]z_\alpha/2=1.64[/tex]  

Using the normal standard table, excel or a calculator we see that:  

[tex]z_{\alpha/2}=1.64[/tex]

Since we have all the values we can replace:

[tex]60 - 1.64\frac{10}{\sqrt{30}}=57.006[/tex]  

[tex]60 + 1.64\frac{10}{\sqrt{30}}=62.994[/tex]  

So on this case the 90% confidence interval would be given by (57.006;62.994)  

Final answer:

To construct the 90% confidence interval for the average number of days it takes to find a job using the website's service, the formula for a confidence interval is applied using the given sample mean of 60 days, population standard deviation of 10 days, and a sample size of 30 customers. The calculated interval is between 57 and 63 days.

Explanation:

To construct a 90% confidence interval for the population mean number of days it takes to find a job using the website's service, we need to use the formula:

CI = \(\bar{x} \pm z*\frac{\sigma}{\sqrt{n}}\)

Where:

\(\bar{x}\) is the sample mean (60 days)

\(z\) is the z-score that corresponds to the desired confidence level (For 90%, \(z=1.645\) from the z-table)

\(\sigma\) is the population standard deviation (10 days)

\(n\) is the sample size (30 customers)

Plugging the values into the formula gives:

CI = 60 \pm 1.645 * (\frac{10}{\sqrt{30}})

Calculating the margin of error:

ME = 1.645 * (\frac{10}{\sqrt{30}}) \approx 3.00

Now compute the confidence interval:

CI = [60 - 3.00, 60 + 3.00]

CI = [57.00, 63.00]

So, we are 90% confident that the population mean number of days it takes to find a job using the website's service is between 57 and 63 days.

From the top of a vertical tower, 331 feet above the surface of the earth, the angle of depression to a doghouse is 28 degrees 8'. How far is it from the doghouse to the foot of the tower?

Answers

Answer:

619.13 feet

Step-by-step explanation:

Please find the attachment.

Let x represent the distance between doghouse to the foot of the tower.

We have been given that from the top of a vertical tower, 331 feet above the surface of the earth, the angle of depression to a doghouse is 28 degrees 8'. We are asked to find the distance between doghouse to the foot of the tower.

First of all, we will convert our given angle into degrees as it is given in degrees and minutes.

We will divide 8 by 60 to convert 8 minutes into degrees as:

[tex]\frac{8}{60}=0.13333[/tex]

The doghouse, tower and angle of depression forms a right triangle with respect to ground, where, 331 feet is opposite side and x is adjacent side to angle 28.13 degrees.

[tex]\text{tan}=\frac{\text{Opposite}}{\text{Adjacent}}[/tex]

[tex]\text{tan}(28.13^{\circ})=\frac{331}{x}[/tex]

[tex]x=\frac{331}{\text{tan}(28.13^{\circ})}[/tex]

[tex]x=\frac{331}{0.534623339864}[/tex]

[tex]x=619.12747783[/tex]

Upon rounding to nearest hundredth, we will get:

[tex]x\approx 619.13[/tex]

Therefore, the doghouse is 619.13 feet far from the foot of the tower.

Management at a seaside resort is publishing a brochure and wants to include a statement about the proportion of clear days during their peak season. Out of a random sample of 150 days from over the last two peak seasons, 117 days were recorded as clear. They want to estimate the proportion of clear days to within a 5% margin of error with a 95% confidence interval. What's the sample size necessary to construct this interval?A. 384B. 264C. 383D. 385E. 263

Answers

Answer: B. 264

Step-by-step explanation:

Formula to calculate the sample size 'n' , if the prior estimate of the population proportion (p) is available:

[tex]n= p(1-p)(\dfrac{z}{E})^2[/tex]

, where z = Critical z-value corresponds to the given confidence interval

E=  margin of error

Let p be the population proportion of clear days.

As per given , we have

Prior sample size : n= 150

Number of clear days in that sample = 117

Prior estimate of the population proportion of clear days = [tex]p=\dfrac{117}{150}[/tex]

E= 0.05

The critical z-value corresponding to 95% confidence interval = z*= 1.95 (By z-table)

Then, the required sample size will be :

[tex]n= \dfrac{117}{150}(1-\dfrac{117}{150})(\dfrac{1.96}{0.05})^2[/tex]

Simplify ,

[tex]n= (0.1716)(39.2)^2[/tex]

[tex]n= 263.687424\approx264[/tex]

Hence, the sample size necessary to construct this interval =264

Thus the correct option is B. 264

The random variable x is the number of occurrences of an event over an interval of ten minutes. It can be assumed that the probability of an occurrence is the same in any two time periods of an equal length. It is known that the mean number of occurrences in ten minutes is 5.3. The probability that there are 8 occurrences in ten minutes is

A. .0241
B. .0771
C. .1126
D. .9107

Answers

Answer:

The probability that there are 8 occurrences in ten minutes is

option B. 0 .0771

Step-by-step explanation:

Given:

Random Variable = x

Mean number of occurrences in ten minutes is 5.3.

The probability of an occurrence is the same in any two time periods of an equal length

To Find:

The probability that there are 8 occurrences in ten minutes  = ?

Solution:

Let X be the number of  occurrences of the event X

[tex]X \sim {Pois} (\lambda)[/tex]

[tex]\lambda = E(X) = 5.3[/tex]

Possion of distribution is given by ,

[tex]P(X=x) = \frac{e^{- \lambda} \lambda^{x}}{x!}[/tex]

Substituting the values,

[tex]P(X=8) = \frac{e^{- 5.3} 5.3^{8}}{8!}[/tex]

[tex]P(X=8) = \frac{(0.004994) ( 622596.904)}{40320}[/tex]

[tex]P(X=8) = \frac{(3109.24894)}{40320}[/tex]

P(X=8) = 0.0771

To find the probability of 8 occurrences in ten minutes with a mean of 5.3, use the Poisson distribution formula to calculate the probability, resulting in approximately 0.0771.

Given: Mean number of occurrences in ten minutes = 5.3

Formula: Probability mass function of a Poisson distribution is given by: P(x) = (e^-λ * λ^x) / x!

Calculations: Plugging in the values, P(X=8) = (e^(-5.3) * 5.3^8) / 8! ≈ 0.0771

Suppose that for all t, a particle moving with constant speed is parameterized by r(t). Given that the length of the path from t = 5 to t = 7 is equal to 8, find the value of the speed, llv(t)ll.

Answers

Answer: value of the speed, llv(t)ll = 4.0

Step-by-step explanation:

Given;

time interval t1 =5, t2= 7

Length of path ( distance) L = 8

Speed = distance travelled/ time taken

Speed = dL/dt

Speed = 8/(t2-t1) = 8/(7-5)

Speed = 8/2

Speed = 4.0

Since it's moving at constant speed the speed = 4.0

A leprechaun places a magic penny under a girl's pillow. The next night there are 2 magic pennies under her pillow. Each night the number of magic pennies doubles. How much money will the girl have after 25 nights? PLEASE HURRY

Answers

Answer:

The girl will have $335,544.32

Step-by-step explanation:

2^25 = 33,554,432

Divide by 100 to turn the amount of pennies into dollars:

33,554,432/100

$335,544.32

A disadvantage of using an arithmetic mean to summarize a set of data is that __________. Select one: a. The arithmetic mean sometimes has two values b. It can be used for interval and ratio data c. It is always different from the median d. It can be biased by one or two extremely small or large values

Answers

Answer:

d. It can be biased by one or two extremely small or large values

Step-by-step explanation:

Specially in a small sample, a single measure can cause a large difference.

For example, you are selling yourself as a tutor, you have five students. 4 of them got good grades, but the other one got 0. The arithmetic mean is not going to be kind to your averages, in virtue of the outlier.

So the correct answer is:

d. It can be biased by one or two extremely small or large values

Final answer:

The arithmetic mean's disadvantage is that extreme values or outliers in the data set can significantly skew the mean. This makes the mean a less accurate reflection of the central tendency or 'average' of the data.

Explanation:

The correct answer to your question is "d. It can be biased by one or two extremely small or large values." The arithmetic mean, often simply called the 'mean', is a type of average most commonly used. It is calculated by adding all numbers in a set and then dividing by the quantity of numbers. While useful, it has a significant disadvantage in its sensitivity to extreme values, also referred to as 'outliers'. If there are one or two extremely large or small numbers in the data set, these can drastically affect the calculated mean, thus not accurately representing the central tendency of the overall data.

Learn more about Arithmetic Mean here:

https://brainly.com/question/36844862

#SPJ3

Suppose the interval ​[4​,6​] is partitioned into n=4 subintervals. What is the subinterval length Δx​? List the grid points x0​, x1​, x2​, x3​, x4. Which points are used for the​left, right, and midpoint Riemann​ sums?

Answers

If a generic interval [tex][a,b][/tex] is partitioned into [tex]n[/tex] subintervals, each one has a length:

[tex]\Delta x = \dfrac{b-a}{n}.[/tex]

In this case, [tex]a = 4[/tex], [tex]b=6[/tex] and [tex]n=4[/tex], so:

[tex]\Delta x = \dfrac{6-4}{4} = \dfrac{2}{4} = \dfrac{1}{2} = 0.5.[/tex]

The grid points are given by:

[tex]x_k = a + k\Delta x, \quad\textrm{with } k \in \{0,1,2,3,4\}.[/tex]

Since [tex]a = 4[/tex] and [tex]\Delta x = 0.5[/tex], we have:

[tex]x_0 = 4 + 0 \times 0.5 = 4 \\x_1 = 4 + 1 \times 0.5 = 4 + 0.5 = 4.5\\x_2 = 4 + 2 \times 0.5 = 4 + 1 = 5\\x_3 = 4 + 3 \times 0.5 = 4 + 1.5 = 5.5\\x_4 = 4 + 4 \times 0.5 = 4 + 2 = 6[/tex]

The [tex]4[/tex] subintervals are of the form [tex]I_k = [x_{k-1}, x_k], \quad\textrm{with } k \in \{1, 2, 3,4\}[/tex]:

[tex]I_1 = [x_0, x_1] = [4,4.5]\\I_2 = [x_1, x_2] = [4.5,5]\\I_3 = [x_2, x_3] = [5,5.5]\\I_4 = [x_3, x_4] = [5.5, 6][/tex]

For the left Riemann sums we will use the left-handed points, namely:

[tex]\{x_0, x_1, x_2, x_3\} = \{4,4.5,5,5.5\}.[/tex]

For the right Riemann sums we will use the right-handed points, namely:

[tex]\{x_1, x_2, x_3, x_4\} = \{4.5,5,5.5,6\}.[/tex]

For the midpoint Riemann sums we will use the average between the two extrema of each subinterval, given by

[tex]I_k \to \tilde{x}_k = \dfrac{x_{k-1}-x_k}{2}, \quad \textrm{with } k \in\{1,2,3,4\}.[/tex]

This gives the midpoints:

[tex]I_1 = [x_0, x_1] = [4,4.5] \to \tilde{x}_1 = \dfrac{x_0 + x_1}{2} = \dfrac{4+4.5}{2} = \dfrac{8.5}{2} = 4.25\\\\I_2 = [x_1, x_2] = [4.5,5] \to \tilde{x}_2 = \dfrac{x_1 + x_2}{2} = \dfrac{4.5+5}{2} = \dfrac{9.5}{2} = 4.75\\\\I_3 = [x_2, x_3] = [5,5.5] \to \tilde{x}_3 = \dfrac{x_2 + x_3}{2} = \dfrac{5+5.5}{2} = \dfrac{10.5}{2} = 5.25\\\\I_4 = [x_3, x_4] = [5.5,6] \to \tilde{x}_4 = \dfrac{x_3 + x_4}{2} = \dfrac{5.5+6}{2} = \dfrac{11.5}{2} = 5.75[/tex]

The points used for the midpoint Riemann sums are therefore:

[tex]\{\tilde{x}_1,\tilde{x}_2,\tilde{x}_3,\tilde{x}_4\} =\{4.25,4.75,5.25,5.75\}.[/tex]

The interval and sub intervals are illustrations of Riemann sums

The length of the sub-intervals is 0.5The grid points are 4, 4.5, 5, 5.5 and 6The midpoints are 4.25, 4.75, 5.25 and 5.75

The given parameters are:

[tex]\mathbf{Interval = [4,6]}[/tex]

[tex]\mathbf{n =4}[/tex] --- sub intervals

(a) The sub interval length

This is calculated as:

[tex]\mathbf{\Delta x = \frac{b - a}{n}}[/tex]

Where:

[tex]\mathbf{[a,b] =[4,6]}[/tex]

So, we have:

[tex]\mathbf{\Delta x = \frac{6 - 4}{4}}[/tex]

[tex]\mathbf{\Delta x = \frac{2}{4}}[/tex]

[tex]\mathbf{\Delta x = 0.5}[/tex]

Hence, the length of the sub-intervals is 0.5

(b) The grid points

This is calculated as:

[tex]\mathbf{x_k = a + k\Delta x}[/tex]

So, we have:

[tex]\mathbf{x_0 = 4 + 0 \times 0.5 = 4}[/tex]

[tex]\mathbf{x_1 = 4 + 1 \times 0.5 = 4.5}[/tex]

[tex]\mathbf{x_2 = 4 + 2 \times 0.5 = 5}[/tex]

[tex]\mathbf{x_3 = 4 + 3 \times 0.5 = 5.5}[/tex]

[tex]\mathbf{x_4 = 4 + 4 \times 0.5 = 6}[/tex]

So, the grid points are 4, 4.5, 5, 5.5 and 6

(c) The left, right and midpoint Riemann sums

The left points are 4, 4.5, 5 and 5.5The right points are 4.5, 5, 5.5 and 6

The midpoint is the average of the left and right points.

So, we have:

[tex]\mathbf{x_0 = 0.5 \times (4 + 4.5) = 4.25}[/tex]

[tex]\mathbf{x_1 = 0.5 \times (4.5 + 5) = 4.75}[/tex]

[tex]\mathbf{x_2 = 0.5 \times (5 + 5.5) = 5.25}[/tex]

[tex]\mathbf{x_3 = 0.5 \times (5.5 + 6) = 5.75}[/tex]

So, the midpoints are 4.25, 4.75, 5.25 and 5.75

Read more about Riemann sums at:

https://brainly.com/question/23960718

A continuous random variable may assume :
a. any numerical value in an interval or collection of intervals.b. finite number of values in a collection of intervals.c. an infinite sequence of values.d. only the positive integer values in an interval.

Answers

Answer:

Option A) any numerical value in an interval or collection of intervals

Step-by-step explanation:

Continuous Random Variable:

A continuous random variable can take any value within an interval.Thus, it can take infinite values since there are infinite numbers in an interval.A continuous variable is a variable whose value is obtained by measuring.Examples: height of students in class , weight of students in class, time it takes to get to school, distance traveled between classes.Thus, the correct meaning of continuous random variable is explained by Option A)

Option A) any numerical value in an interval or collection of intervals

Final answer:

A continuous random variable can take on any numerical value within a given range or collection of ranges, and it's a characteristic feature of it to take an infinite number of values in any interval. Some examples of this can be a person's height, time, temperature, and weight in physics.

Explanation:

A continuous random variable is a type of random variable that can assume any numerical value in a given interval or collection of intervals, making option a correct. This is in contrast to a discrete random variable, which can only take on a finite number of values. A key characteristic of continuous random variables is that they can take on an infinite number of values in any interval.

For example, the height of a person can be treated as a continuous variable, since it can theoretically take any value within a certain range, not just whole number values. The same applies to variables such as time, temperature, and weight in physics.

Learn more about Continuous Random Variable here:

https://brainly.com/question/32867130

#SPJ6

ANYTHING WILL HELP!!!! ASAP!!!!

Answers

Washington High School won the meet.

Johnson High School came in second with 159 points.

Difference between first and second was 3 points.

Step-by-step explanation:

At a particular swim meet, the details of the points which were awarded to the first three places finish are given.

First place finish got 10 points.Second place finish got 8 points.Third place finish got 7 points.

To find the total number of points scored by each school is equal to sum of multiplying the respective points which were awarded to number of respective places finish.  

i.e. Washington High School had 10 first places finish, so total points for first place finish [tex]= 10 \times10=100[/tex] points.

Similarly, for second places finish = [tex]6\times 8=48[/tex]

and for third places finish = [tex]=2\times 7=14[/tex]

Therefore, Washington High School had total points = 100 + 48 + 14 = 162 points

By using this method, we can make the matrices (Please refer the below attachment).

From the matrices,

Total number of points:

Washington High School = 162 pointsJohnson High School = 159 pointsRoosevelt High School = 108 pointsLewis High School = 96 points

Among these scores of four schools, 162 is the highest score. So, Washington High School won the meet.

Johnson High School came in second with 159 points.

Difference between first and second = 162 - 159 = 3 points.

We guess, based on historical data, that 30% of graduating high-school seniors in a large city will have completed a first-year calculus course. What's the minimum sample size needed to construct a 95% confidence interval for a proportion with a margin of error of 2.5%?

Answers

Answer:

[tex]n=\frac{0.3(1-0.3)}{(\frac{0.025}{1.96})^2}=1290.78[/tex]  

And rounded up we have that n=1291

Step-by-step explanation:

1) Previous concepts

A confidence interval is "a range of values that’s likely to include a population value with a certain degree of confidence. It is often expressed a % whereby a population means lies between an upper and lower interval".  

The margin of error is the range of values below and above the sample statistic in a confidence interval.  

Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".  

The population proportion have the following distribution

[tex]p \sim N(p,\sqrt{\frac{p(1-p)}{n}})[/tex]

2) Solution to the problem

In order to find the critical value we need to take in count that we are finding the interval for a proportion, so on this case we need to use the z distribution. Since our interval is at 95% of confidence, our significance level would be given by [tex]\alpha=1-0.95=0.05[/tex] and [tex]\alpha/2 =0.025[/tex]. And the critical value would be given by:

[tex]z_{\alpha/2}=-1.96, z_{1-\alpha/2}=1.96[/tex]

The margin of error for the proportion interval is given by this formula:  

[tex] ME=z_{\alpha/2}\sqrt{\frac{\hat p (1-\hat p)}{n}}[/tex]    (a)  

And on this case we have that [tex]ME =\pm 0.025[/tex] and we are interested in order to find the value of n, if we solve n from equation (a) we got:  

[tex]n=\frac{\hat p (1-\hat p)}{(\frac{ME}{z})^2}[/tex]   (b)  

And replacing into equation (b) the values from part a we got:

[tex]n=\frac{0.3(1-0.3)}{(\frac{0.025}{1.96})^2}=1290.78[/tex]  

And rounded up we have that n=1291

Which function represents a vertical stretch of an exponential function? f (x) = 3 (one-half) Superscript x f (x) = one-half (3) Superscript x f (x) = (3) Superscript 2 x f (x) = 3 Superscript (one-half x)

Answers

Answer:

f(x) = 3[tex](\frac{1}{2})^{x}[/tex]

Step-by-step explanation:

hope it helps!

Final answer:

The function that represents a vertical stretch of an exponential function is f(x) = (3)^x.

Explanation:

The function that represents a vertical stretch of an exponential function is f(x) = (3)x.

In this function, the base of the exponential term is 3, and the exponent, x, determines the position on the graph. When the value of x increases, the function values also increase at an exponential rate.

For example, when x = 1, f(1) = (3)1 = 3. When x = 2, f(2) = (3)2 = 9. The function values double with each increase of x.

Verify that P = Ce^t /1 + Ce^t is a one-parameter family of solutions to the differential equation dP dt = P(1 − P).

Answers

Answer:

See verification below

Step-by-step explanation:

We can differentiate P(t) respect to t with usual rules (quotient, exponential, and sum) and rearrange the result. First, note that

[tex]1-P=1-\frac{ce^t}{1+ce^t}=\frac{1+ce^t-ce^t}{1+ce^t}=\frac{1}{1+ce^t}[/tex]

Now, differentiate to obtain

[tex]\frac{dP}{dt}=(\frac{ce^t}{1+ce^t})'=\frac{(ce^t)'(1+ce^t)-(ce^t)(1+ce^t)'}{(1+ce^t)^2}[/tex]

[tex]=\frac{(ce^t)(1+ce^t)-(ce^t)(ce^t)}{(1+ce^t)^2}=\frac{ce^t+ce^{2t}-ce^{2t}}{(1+ce^t)^2}=\frac{ce^t}{(1+ce^t)^2}[/tex]

To obtain the required form, extract a factor in both the numerator and denominator:

[tex]\frac{dP}{dt}=\frac{ce^t}{1+ce^t}\frac{1}{1+ce^t}=P(1-P)[/tex]

Help please!!! 20 points will mark brainliest!! :)

Answers

Answer:

The equation has zeroes at -4, 0 and 4 and is a minimum cubic degree or a 3 degree equation.

Step-by-step explanation:

The polynomial has roots at places where f(x) cuts the x axis.

The function cuts the x-axis at 3 points: 4, -4, and 0.

It cuts the axis at the point, x=0; x=4; x=-4

Therefore, the points equation has to be of the form, k*x*(x-4)*(x+4)*p(x)

where k is any arbitrary constant and p(x) is a polynomial of any degree depending on what the equation does in the region and (5,∞) and (-∞,-5).

Therefore, the equation has zeroes at -4, 0 and 4 and is a minimum cubic degree or a 3 degree equation.

A random sample of the amounts for 22 purchases was taken. The mean was ​$42.97​, the standard deviation was ​$22.82​, and the margin of error for a 95​% confidence interval was ​$10.12. Assume that t Subscript n minus 1 Superscript starequals2.0 for the​ 95% confidence intervals. ​a) To reduce the margin of error to about ​$5​, how large would the sample size have to​ be? ​b) How large would the sample size have to be to reduce the margin of error to ​$1.0​?

Answers

Answer: a) 84 and b ) 2084

Step-by-step explanation:

Given : Sample standard deviation : s= $22.82

(Population standard deviation is unknown ) , so we use t-test.

Critical value or the​ 95% confidence intervals :[tex]t_{n-1}*=2.0[/tex]

Formula to find the sample size :

[tex]n=(\dfrac{t^*\cdot s}{E})^2[/tex]

a) E = 5

[tex]n=(\dfrac{(2)\cdot 22.82}{5})^2[/tex]

[tex]n=(9.128)^2=83.320384\approx84[/tex]

i.e. Required sample size : n= 84

b)  E = 1

[tex]n=(\dfrac{(2)\cdot 22.82}{1})^2[/tex]

[tex]n=(45.64)^2=2083.0096\approx2084[/tex]

i.e. Required sample size : n= 2084

The side of the base of a square prism is increasing at a rate of 5 meters per second and the height of the prism as decreasing at a rate of 2 meters per second. At a certain instant, the base's side is 6 meters and the height is 7 meters. What is the rate of change of the volume of the prism at that instant fin cubic meters per second?

A. -348
B. 492
C. -492
D. 348

Answers

Answer:

D. 348

Step-by-step explanation:

The volume of the square prisma is given by the following formula:

[tex]V = s^{2}h[/tex]

In which h is the height, and s is the side of the base.

Let's use implicit derivatives to solve this problem:

[tex]\frac{dV}{dt} = 2sh\frac{ds}{dt} + s^{2}\frac{dh}{dt}[/tex]

In this problem, we have that:

[tex]\frac{ds}{dt} = 5, \frac{dh}{dt} = -2, h = 7, s = 6[/tex]

So

[tex]\frac{dV}{dt} = 2sh\frac{ds}{dt} + s^{2}\frac{dh}{dt}[/tex]

[tex]\frac{dV}{dt} = 2*6*7*5 + (6)^{2}*(-2) = 348[/tex]

So the correct answer is:

D. 348

Shane receives an hourly wage of $30.40 an hour as an emergency room nurse. When called in at night, he receives time and half. How much does he make if he works 15 hours at night?​

Answers

$685.50. He would be making $45.70 (time and a half) and that multiplied by 15 is $685.50

Mutliply his hourly rate by 1.5 to find his night pay:

30.40 x 1.5 = $45.60 per hour at night.

Multiply his rate by number of hours:

45.60 x 15 = $684

What is 6 to the power of 8 in exponential form?

Answers

Answer: 1.7 x 10^6

Step-by-step explanation:

6^8 = 1,679,616

1,679,616 = 1.7 x 10^6

Considered safe for agricultural use. A well in Texas is used to water crops. This well is tested on a regular basis for arsenic. A random sample of 36 tests gave a sample mean of = 7.3 ppb arsenic, with s = 1.9 ppb. Does this information indicate that the mean level of arsenic in this well is less than 8 ppb? Use a 0.01 level of signifcance..

Answers

Answer:

This information indicates that the mean level of arsenic in this well is less than 8 ppbat  0.01 level of signifcance..

Step-by-step explanation:

Given that a well in Texas is used to water crops.

This well is tested on a regular basis for arsenic.

A random sample of 36 tests gave a sample mean of = 7.3 ppb arsenic, with s = 1.9 ppb

H0: Sample mean = 8

Ha: Sample mean <8

(left tailed test at 1% level)

Mean difference =-0.70

Std error of mean = [tex]\frac{1.9}{\sqrt{36} } \\=0.3167[/tex]

Test statistic t = -2.204

df = 35

p value = 0.0171

Since p >0.01 we accept H0

This information indicates that the mean level of arsenic in this well is less than 8 ppbat  0.01 level of signifcance..

A scientist was interested in studying if students political beliefs change as they go through college. Two hundred randomly selected students were asked before they entered college if they would consider themselves liberal or conservative. Four years later, the same two hundred students were asked if they would consider themselves, liberal or conservative. The scientist decided to perform McNemar's test. The data is below. What is the null hypothesis? After College Before College Liberal Conservative Liberal 80 15 Conservative 20 85

A. -0.85 or 0.85

B. -0.39 or 0.39

C. -9.75 or -9.75

D. 1.96 or -1.96

Answers

The null hypothesis in this considered experiment is: There is no change in their political beliefs as they go through college.

How to form the hypotheses?

There are two hypotheses. First one is called null hypothesis and it is chosen such that it predicts nullity or no change in a thing. It is usually the hypothesis against which we do the test. The hypothesis which we put against null hypothesis is alternate hypothesis.

Null hypothesis is the one which researchers try to disprove.

Here, it is specified that the scientist wants to study if students political beliefs change as they go through college. He wants to test if there are changes in the proportions of people who are liberal( or conservative).

Given that:

100 students before and after were asked their policial belief, as shown in table:

                               Liberal                Conservative

After college              80                       20

Before college           85                       15

Proportion of liberal = 1 - proportion of conservatives

So we will symbolize the hypotheses in terms of one of them, let it be proportions of liberals.

Sample size = 100

Favorable cases = Number of people from sample who consider themselves liberal. = X (say)

After college:

Sample proportion is: [tex]\hat{p}_1 = \dfrac{X}{N} = \dfrac{80}{100} = 0.8[/tex]

Before college:

Sample proportion is: [tex]\hat{p}_2 = \dfrac{X}{N} = \dfrac{85}{100} = 0.85[/tex]

Let p1 and p2 be the population proportion of people believing themself liberal after and before college respectively.

Then, the null hypothesis will assume that the claim of difference in belief the scientist wants to test is false, and therfore,

[tex]H_0: p_1 = p_2[/tex] or [tex]H_0: p_1 - p_2 = 0[/tex] (no difference, proportions are same, indicating that belief of students doesn't change much, as d)

Thus, the null hypothesis in this considered experiment is: There is no change in their political beliefs as they go through college.

Learn more about null and alternative hypothesis here:

https://brainly.com/question/18831983

There are 3 alternative routes by which you may drive to work: Alabaster Street, Brillantine Street, and Clancy Street. It is the beginning of rush hour, and by experience Alabaster street will be closed by a car crash on average in 25 minutes, Brillantine street in 50 minutes, and Clancy Street in 40 minutes. Accident times are completely unpredictable. If you leave for work in one hour (60 minutes), what is the probability that (at the moment you leave) a route to work will still be open?

Answers

The probability that at least one route to work will still be open is [tex]\( \frac{209}{216} \)[/tex] when leaving.

To find the probability that at least one route to work will still be open when you leave for work, we need to find the probability that none of the streets will be closed within the next hour.

Let [tex]\( A \)[/tex], [tex]\( B \)[/tex], and [tex]\( C \)[/tex] represent the events that Alabaster, Brillantine, and Clancy Streets are closed due to accidents within the next hour, respectively.

The probability of each street being closed within the next hour is:

[tex]\[ P(A) = \frac{25}{60} = \frac{5}{12} \][/tex]

[tex]\[ P(B) = \frac{50}{60} = \frac{5}{6} \][/tex]

[tex]\[ P(C) = \frac{40}{60} = \frac{2}{3} \][/tex]

Since the accidents on each street are independent events, the probability that all three streets remain open is the product of the probabilities that each street remains open:

[tex]\[ P(\text{})[/tex] = [tex]P(\neg A \cap \neg B \cap \neg C) = P(\neg A) \times P(\neg B) \times P(\neg C) ][/tex]

where [tex]\( \neg A \)[/tex], [tex]\( \neg B \)[/tex], and[tex]\( \neg C \)[/tex] represent the complementary events that the streets are not closed.

So, we have:

[tex]\[ P(\text{})[/tex] = [tex](1 - P(A)) \times (1 - P(B)) \times (1 - P(C)) ][/tex]

[tex]\[ = \left(1 - \frac{5}{12}\right) \times \left(1 - \frac{5}{6}\right) \times \left(1 - \frac{2}{3}\right) \][/tex]

[tex]\[ = \left(\frac{7}{12}\right) \times \left(\frac{1}{6}\right) \times \left(\frac{1}{3}\right) \][/tex]

[tex]\[ = \frac{7}{12} \times \frac{1}{6} \times \frac{1}{3} \]\[ = \frac{7}{216} \][/tex]

Therefore, the probability that at least one route to work will still be open when you leave for work is [tex]\( 1 - \frac{7}{216} = \frac{209}{216} \)[/tex].

how much mg of a metal containing 4% silver must be combined with 11 mg of a metal containing 38% silver to form an alloy containing 26% silver

Answers

Answer:

6 mg of the metal needs to be added.

Step-by-step explanation:

Let the amount (in mg) of metal that needs to be added by y.

Therefore, the amount of silver in the above metal is 0.04y.

Prior to mixing, 11 mg of a metal contained 38% of silver (Given).

Therefore, the amount of silver before= [tex]\frac{38}{100}*11[/tex]= 4.18 mg

The total amount of silver after mixing, 4.18 + 0.04y mg

The total amount of metal after mixing, 11 + y mg

New percentage of silver = 26% .

Thus, [tex]\frac{4.18+0.04y}{11+y}*100= 26[/tex]

[tex](4.18 +0.04 y) * 100 = 26 *(11 +y)[/tex]

[tex]418+4y=286+26y[/tex]

[tex]132=22y[/tex]

y=6 mg

Therefore, the amount of metal that needs to be added is 6 mg.

Assume that the weights of Chinook Salmon in the Columbia River are normally distributed. You randomly catch and weigh 40 such salmon. The mean weight from your sample is 23.6 pounds with a standard deviation of 3.5 pounds. Test the claim that the mean weight of Columbia River salmon is greater than 23 pounds. Test this claim at the 0.10 significance level.
(a) What type of test is this?i) This is a right-tailed test.ii) This is a two-tailed test. iii) This is a left-tailed test.(b) What is the test statistic? Round your answer to 2 decimal places.

Answers

Answer:

a) i) This is a right-tailed test.

b)

[tex]\text{Test statistic} = 1.08[/tex]

Step-by-step explanation:

We are given the following in the question:

Population mean, μ = 23 pounds

Sample mean, [tex]\bar{x}[/tex] = 23.6 pounds

Sample size, n = 40

Alpha, α = 0.10

Sample standard deviation, s = 3.5 pounds

First, we design the null and the alternate hypothesis

[tex]H_{0}: \mu = 23\text{ pounds}\\H_A: \mu > 23\text{ pounds}[/tex]

This is a one tailed(right).

Formula:

[tex]\text{Test statistic} = \displaystyle\frac{\bar{x} - \mu}{\frac{s}{\sqrt{n}} }[/tex]

Putting all the values, we have

[tex]\text{Test statistic} = \displaystyle\frac{23.6 - 23}{\frac{3.5}{\sqrt{40}} } = 1.08[/tex]

What percentage of youth sport participants has experienced a sport related injury?

A.50%100%
B. 75%
C. 25%
D. 95%

Answers

Answer:

B.75%

Step-by-step explanation:

Answer:

A. 50%

Step-by-step explanation:

about 50% b/c over half the people who play sports all get injuries

Audrey, an astronomer is searching for extra-solar planets using the technique of relativistic lensing. Though there are believed to be a very large number of planets that can be found this way, actually finding one takes time and luck; and finding one planet does not help at all with finding planets of other stars in the same part of the sky. Audrey is good at it, and finds one planet at a time, on average once every three months.

a.) Find the expected value and standard deviation of the number of planets she will find in the next two years.
b.) When she finds her sixth new planet, she will be eligible for a prize. Find the expected value and standard deviation of the amount of time until she is eligible for that prize.
c.) Find the probability that she will become eligible for that prize within one year.

Answers

Answer:

Step-by-step explanation:

The model [tex]N (t)[/tex], the number of planets found up to time [tex]t[/tex], as a Poisson process. So, the [tex]N (t)[/tex] has distribution of Poison distribution with parameter [tex](\lambda t)[/tex]

a)

The mean for a month is, [tex]\lambda = \frac{1}{3}[/tex] per month

[tex]E[N(t)]= \lambda t\\\\=\frac{1}{3}

(24)\\\\=8[/tex]

(Here. t = 24)

For Poisson process mean and variance are same,

[tex]Var[N (t)]= Var[N(24)]\\= E [N (24)]\\=8[/tex]

 

(Poisson distribution mean and variance equal)

 

The standard deviation of the number of planets is,

[tex]\sigma( 24 )] =\sqrt{Var[ N(24)]}=\sqrt{8}= 2.828

[/tex]

b)

For the Poisson process the intervals between events(finding a new planet) have  independent  exponential  distribution with parameter [tex]\lambda[/tex]. The  sum  of [tex]K[/tex] of these  independent exponential has distribution Gamma [tex](K, \lambda)[/tex].

From the given information, [tex]k = 6[/tex] and [tex]\lambda =\frac{1}{3}

[/tex]

Calculate the expected value.

[tex]E(x)=\frac{\alpha}{\beta}\\\\=\frac{K}{\lambda}

\\\\=\frac{6}{\frac{1}{3}}\\\\=18[/tex]

(Here, [tex]\alpha =k[/tex] and [tex]\beta=\lambda[/tex])                                                                      

C)

Calculate the probability that she will become eligible for the prize within one year.

Here, 1 year is equal to 12 months.

P(X ≤ 12) = (1/Г  (k)λ^k)(x)^(k-1).(e)^(-x/λ)

[tex]=\frac{1}{Г  (6)(\frac{1}{3})^6}(12)^{6-1}e^{-36}\\\\=0.2148696\\=0.2419\\=21.49%[/tex]

Hence, the required probability is 0.2149 or 21.49%

Final answer:

We can calculate the expected value and standard deviation of the number of planets Audrey will find in the next two years using probability and statistics. Using geometric distribution, we can also calculate the expected value and standard deviation of the amount of time until Audrey is eligible for a prize after finding her sixth new planet. Finally, we can calculate the probability of Audrey becoming eligible for the prize within one year using the binomial distribution formula.

Explanation:

To find the expected value and standard deviation of the number of planets Audrey will find in the next two years, we can use the concepts of probability and statistics. Since she finds one planet every three months on average, the expected value can be calculated by multiplying the average number of planets found per month (1/3) by the number of months in two years (24). The standard deviation can be calculated using the formula sqrt(n * p * q), where n is the number of trials, p is the probability of success, and q is the probability of failure.

To find the expected value and standard deviation of the amount of time until Audrey is eligible for the prize after finding her sixth new planet, we can use the concept of geometric distribution. The expected value can be calculated by taking the reciprocal of the probability of success (1/6) and the standard deviation can be calculated using the formula sqrt((1-p) / (p^2)).

To find the probability that Audrey will become eligible for the prize within one year, we can calculate the cumulative probability of finding six or more new planets in one year using the binomial distribution formula.

Learn more about Expected value and standard deviation here:

https://brainly.com/question/32256698

#SPJ3

Complete the two column proof Given: 22= 24,m_2 = 110°
Prove: m 23 = 70°
Statement
Proof
22 24, mZ2=1109
Given
m 2 2 = m 24
Definition of congruent angles
m 24 = 1100
m 23 and m 24 are a linear pair
Definition of a linear pair (shown in
diagram)​

Answers

Step-by-step explanation:

I took 3 indicated as 5 and its adjacent angle to be 3

<2 = <4

As <2 =<3( corresponding angle)

And <3 = <4 ( Vertically opp.angle)

hence <2 = <4

<2 =>110

so , <4 = 110

So, <4 =>110

As <4 and <5 form linear pair

So <4 + <5 =>180

<5 = 180 -110 =>70

As i took <5 as replacing angle to <3

So According to Question fig

<3 =>70

Hence proved

This exercise uses the population growth model. It is observed that a certain bacteria culture has a relative growth rate of 15% per hour, but in the presence of an antibiotic the relative growth rate is reduced to 8% per hour. The initial number of bacteria in the culture is 28. Find the projected population after 24 hours for the following conditions. (Round your answers to the nearest whole number.) (a) No antibiotic is present, so the relative growth rate is 15%. (b) An antibiotic is present in the culture, so the relative growth rate is reduced to 8%.

Answers

Answer:

a) P(24) = 1025.

b) P(24) = 191.

Step-by-step explanation:

This population can be modeled by the following exponential model.

[tex]P(t) = P_{0}e^{rt}[/tex]

In which P(t) is the population after t hours, [tex]P_{0}[/tex] is the initial population and r is the decimal growth rate.

The initial number of bacteria in the culture is 28. This means that [tex]P_{0} = 28[/tex].

Population after 24 hours.

(a) No antibiotic is present, so the relative growth rate is 15%.

So r = 0.15.

[tex]P(t) = P_{0}e^{rt}[/tex]

[tex]P(24) = 28e^{0.15*24} = 1024.75[/tex]

(b) An antibiotic is present in the culture, so the relative growth rate is reduced to 8%.

So r = 0.08.

[tex]P(t) = P_{0}e^{rt}[/tex]

[tex]P(24) = 28e^{0.08*24} = 190.99[/tex]

On the average, 1.6 customers per minute arrive at any one of the checkout counters of Sunshine food market.

What type of probability distribution can be used to find out the probability that there will be no customers arriving at a checkout counter in 10 minutes?
-Poisson distribution
-Normal distribution
-Binomial distribution
-None of these choices.

Answers

the answer would easily be Poisson distribution
Other Questions
define thermodynamics ??? Saunjani states that only 7,500 women graduated with degrees in computer science last year yet women make up 85% of all consumer purchases and use social media at a rate 600% more than men. How do you feel about these statistics? Sonja is riding her bike. She takes her feetoff the pedals to freewheel down a hill.Describe the energy transfers that take place as the bike travels down the hill,Ignore friction and air resistance. If 84 grams of sodium chloride reacts with an excess amount of magnesium oxide, how many grams of sodium oxide will be produced Central to Renaissance thought was a(n)__________.a. fascination with the ancient world. b. deeply religious desire to withdraw from the world. c. desire to re-create the glory of Byzantium. d. appreciation for the art and thought of the middle ages. e. appreciation of secular Confucian thought that had been brought about by closer ties to China. 2.73 A fan within an insulated duct delivers moist air at the duct exit at 358C, 50% relative humidity, and a volumetric flow rate of 0.4 m3 /s. At steady state, the power input to the fan is 1.7 kW. The pressure in the duct is nearly 1 atm throughout. Using the psychrometric chart, determine the temperature, in 8C, and relative humidity at the duct inlet. Uber and Lyft customers often complain about the practice of ""surge"" or ""prime-time"" pricing used by these companies during periods of peak demand. This is an example of a __________ pricing policy. Which of the following statements is true?1. The 2s orbital in the hydrogen atom is larger than the 3s orbital also in the hydrogen atom.2. The hydrogen atom has quantized energy levels.3. The Bohr model of the hydrogen atom has been found to be incorrect.4. An orbital is the same as a Bohr orbit. 5. The third energy level has three sublevels - the s, p, and d sublevels. A person is straining to lift a large crate, without success because it is too heavy. We denote the forces on the crate as follows: P is the upward force the person exerts on the crate, C is the vertical contact force exerted on the crate by the floor, and W is the weight of the crate. How are the magnitudes of these forces related while the person is trying unsuccessfully to lift the crate? A company's stock was selling at$16 a share. A month later, it wasselling at $20 a share. What isthe percent increase?[?]% Hundreds of millions of global consumers now enjoy a level of purchasing power that's sufficient to let them afford high-quality products-except for big-ticket items such as college educations, housing, or luxury cars. This consumer group, known as the ________, tend to buy affordable cars rather than luxury cars mathematics help plz Conduct the appropriate hypothesis test and compute the test statistic. A company that produces fishing line undergoes random testing to see if their fishing line holds up to the advertised specifications. Currently they are producing 30-pound test line and 20 randomly selected pieces are selected to test the strength. The 20 pieces broke with an average force of 29.1 pounds and a sample standard deviation of 2 pounds. Assuming that the strength of the fishing line is normally distributed, perform the appropriate hypothesis test at a 0.05 significance level in order to determine whether there is sufficient sample evidence to conclude the fishing line breaks with an average force of less than 30 pounds.a. No, because the test statistic is -2.01.b. No, because the test statistic is -2.52c. Yes, because the test statistic is -2.52d. Cannot be determined Yes, because the test statistic is -2.01 A person leaves her camp at 7:00 a.m. to hike back to her car. The distance from the car in kilometers y after x hours of hiking can be modeled by the linear function y = 3 x + 18 . What does the x -intercept of the function mean. what did martin luther mean when he said "salvation not works, gets you to heaven" Accounts Payable 420 Accounts Receivable 3,200 Capital Stock 240 Cash 100 Cost of Goods Sold 600 Inventory 380 Long-term Debt 4,640 Net Income 280 Property, Plant, and Equipment (net) 1,400 Retained Earnings (220) Sales 3,000 Note: The retained earnings amount reported is as of the END of the year (after the closing entries have been made). The number of shares outstanding is 100. Compute BOOK VALUE PER SHARE. Why can we infer that Lighting and Thunder live on the "far end of town" at the opening of the story? A)Because they have chosen to banish themselves from the company of others due to the trouble they cause. B)Because the king has banished them to that spot due to Lightning's notorious destructiveness. C)Because the people have demanded that they stay away because they're too loud and frightening to witness. Eliminate D)Because they prefer to live close to the natural world. You decide to open a retirement account at your local bank that pays 8%/year/month (8% per year compounded monthly). For the next 20 years you will deposit $400 per month into the account, with all deposits and withdrawls occurring at the end of the month. On the day of the last deposit, you will retire. Your expenses during the first year of retirement will be covered by your company's retirement plan. As such, your first withdrawal from your retirement account will occur on the day exactly 12 months after the last deposit.a) What monthly withdrawal can you make if you want the account to last 15 years?b) What monthly withdrawal can you make if you want the account to last forever (with infinite withdrawals)? 1. Question: What is the number of the parking space covered by the car?20 seconds to solve the problem!will get brainiest ;b All of your teammates are dedicated to the project. They put in the time and effort to complete their individual assignments and to be adequately prepared for team meetings. However, this time and effort does not seem to translate into effectively sharing information. Which of the following actions is most likely to improve your teams information sharing? Steam Workshop Downloader