Mathematics, 03.06.2020 05:57 khannie

In a study of cell phone use and brain hemispheric dominance, an Internet survey was e-mailed to 5000 subjects randomly selected from an online group involved with ears. 717 surveys were returned. Use a 0.01 significance level to test the claim that the return rate is less than 15%.

Answers: 3

Show answers

Answers

Answer from: gray4675

As the P-value (0.086) is greater than the significance level (0.01), the effect is not significant.

The null hypothesis failed to be rejected.

There is not enough evidence to support the claim that the return rate is less than 15%.

Step-by-step explanation:

This is a hypothesis test for a proportion.

The claim is that the return rate is less than 15%.

Then, the null and alternative hypothesis are:

$H_0: \pi=0.15\\\\H_a:\pi$

The significance level is 0.01.

The sample has a size n=5000.

The sample proportion is p=0.143.

p=X/n=717/5000=0.143

The standard error of the proportion is:

$\sigma_p=\sqrt{\dfrac{\pi(1-\pi)}{n}}=\sqrt{\dfrac{0.15*0.85}{5000}}\\\\\\ \sigma_p=\sqrt{0.000026}=0.005$

Then, we can calculate the z-statistic as:

$z=\dfrac{p-\pi+0.5/n}{\sigma_p}=\dfrac{0.143-0.15+0.5/5000}{0.005}=\dfrac{-0.007}{0.005}=-1.366$

This test is a left-tailed test, so the P-value for this test is calculated as:

P-value=P(z

Answer from: aliciagore

$z=\frac{0.1434 -0.15}{\sqrt{\frac{0.15(1-0.15)}{5000}}}=-1.307$

Now we can calculate the p value with the following probability:

p_v =P(z

For this case the p value is lower than the significance level provided of 0.1 so then we can reject the null hypothesis and we can conclude that the the return rate is significantly less than 15%.

Step-by-step explanation:

Information provided

n=5000 represent the random sample taken

X=717 represent the surveys returned

$\hat p=\frac{717}{5000}=0.1434$ estimated proportion of urvyes returned

p_o=0.15 is the value to verify

$\alpha=0.01$ represent the significance level

z would represent the statistic

p_v represent the p value

System of hypothesis

We want to verify if the return rate is less than 15% the system of hypothesis are.:

Null hypothesis: $p \geq 0.15$

Alternative hypothesis: p < 0.15

The statistic is given by:

$z=\frac{\hat p -p_o}{\sqrt{\frac{p_o (1-p_o)}{n}}}$ (1)

Replacing the info we got:

$z=\frac{0.1434 -0.15}{\sqrt{\frac{0.15(1-0.15)}{5000}}}=-1.307$

Now we can calculate the p value with the following probability:

p_v =P(z

For this case the p value is lower than the significance level provided of 0.1 so then we can reject the null hypothesis and we can conclude that the the return rate is significantly less than 15%.

Answer from: Quest

choice b is correct

step-by-step explanation:

we have been given the following system of linear inequalities;

$y< -2x+4$

$y< x+3$

$x< 3$

we are required to graphically determine the solution to these system of inequalities. using a graphing tool, the solution is as shown in the attachment below;

Which graph represents the following system of inequalities?

Answer from: Quest

the equation cos(35) =a/25 can be used to find the length of bc what is the length of bc? round to the nearest tenth

step-by-step explanation:

Another question on Mathematics

Mathematics, 21.06.2019 15:30

Hurry and answer this! circle x with a radius of 6 units and circle y with a radius of 2 units are shown which steps would prove the circles similar? translate the circles so they share a common center point, and dilate circle y by a scale factor of 4. translate the circles so the center of one circle rests on the edge of the other circle, and dilate circle y by a scale factor of 4. translate the circles so they share a common center point, and dilate circle y by a scale factor of 3. translate the circles so the center of one circle rests on the edge of the other circle, and dilate circle y by a scale factor of 3

Answers: 1

Answer

Mathematics, 21.06.2019 23:00

Someone answer this asap for gabriella uses the current exchange rate to write the function, h(x), where x is the number of u.s. dollars and h(x) is the number of euros, the european union currency. she checks the rate and finds that h(100) = 7.5. which statement best describes what h(100) = 75 signifies? a. gabriella averages 7.5 u.s. dollars for every 100 euros. b. gabriella averages 100 u.s. dollars for every 25 euros. c. gabriella can exchange 75 u.s. dollars for 100 euros. d. gabriella can exchange 100 u.s. dollars for 75 euros.

Answers: 1

Answer

Mathematics, 22.06.2019 01:00

Pentagon abcde is dilated according to the rule do,3(x,y) to create the image pentagon a'b'c'd'e', which is shown on the graph. what are the coordinates of point a of the pre-image? a) (-1, 1)b) (-1, 2)c) (-9, 6)d) (-9, 18)

Answers: 3

Answer

Mathematics, 22.06.2019 03:20

The equation ip| = 2 represents the total number of points that can be earned or lost during one turn of a game. which best describes how many points can be earned or lost during one turn?

Answers: 1

Answer

You know the right answer?

In a study of cell phone use and brain hemispheric dominance, an Internet survey was e-mailed to 500...

Questions