Mathematics, 22.07.2021 20:40 jessnolonger

An automobile manufacturer has given its jeep a 51.3 miles/gallon (MPG) rating. An independent testing firm has been contracted to test the actual MPG for this jeep since it is believed that the jeep has an incorrect manufacturer's MPG rating. After testing 230 jeeps, they found a mean MPG of 51.1. Assume the population variance is known to be 6.25. A level of significance of 0.02 will be used. Make the decision to reject or fail to reject the null hypothesis.

Answers: 1

Show answers

Answers

Answer from: Diamond4614

The p-value of the test is 0.2262 > 0.02, which means that the decision is to fail to reject the null hypothesis.

Step-by-step explanation:

An automobile manufacturer has given its jeep a 51.3 miles/gallon (MPG) rating.

At the null hypothesis, we test if the mean is of 51.3, that is:

$H_0: \mu = 51.3$

An independent testing firm has been contracted to test the actual MPG for this jeep since it is believed that the jeep has an incorrect manufacturer's MPG rating.

This means that at the alternative hypothesis, we test if the mean is different of 51.3, that is:

$H_0: \mu \neq 51.3$

The test statistic is:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

In which X is the sample mean, $\mu$ is the value tested at the null hypothesis, $\sigma$ is the standard deviation and n is the size of the sample.

51.3 is tested at the null hypothesis:

This means that $\mu = 51.3$

After testing 230 jeeps, they found a mean MPG of 51.1. Assume the population variance is known to be 6.25.

This means that $n = 230, X = 51.1, \sigma = \sqrt{6.25} = 2.5$

Value of the test statistic:

$z = \frac{X - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{51.1 - 51.3}{\frac{2.5}{\sqrt{230}}}$

z = -1.21

P-value of the test and decision:

The p-value of the test is the probability of the sample mean differing from 51.1 by at least 0.2, which is P(|z| > 1.21), which is 2 multiplied by the p-value of z = -1.21.

Looking at the z-table, z = -1.21 has a p-value of 0.1131.

2*0.1131 = 0.2262

The p-value of the test is 0.2262 > 0.02, which means that the decision is to fail to reject the null hypothesis.

Answer from: Quest

answer rather than having to add and subtract the measurements of the semi-circle, notice that the semicircle to the left of ad is actually identical in area to the blank semicircle-shaped space to the left of bc. so if we transferred the red semicircle into the blank space, we would end up with a square of side length 24 cm. the area of a square is s^2 = 24^2 = 676 cm^2.

u also answered this so i think u would know but i am here to

put in or use mine

For the figures below, assume they are made of semicircles, quarter circles and squares. for each sh

Answer from: Quest

pretty sure 750 each month!

step-by-step explanation:

Another question on Mathematics

Mathematics, 20.06.2019 18:02

Lin is shopping for a couch with her dad and heard him ask the salesperson “how much is your commission? ” the salesperson says that her commission is 5 1/2% of the selling price. a.how much commission will the salesperson earn by selling a couch for $495? b.how much money will the store get from the sale of the couch?

Answers: 1

Answer

Mathematics, 21.06.2019 17:10

The number of chocolate chips in an 18-ounce bag of chocolate chip cookies is approximately normally distributed with a mean of 1252 chips and standard deviation 129 chips. (a) what is the probability that a randomly selected bag contains between 1100 and 1500 chocolate chips, inclusive? (b) what is the probability that a randomly selected bag contains fewer than 1125 chocolate chips? (c) what proportion of bags contains more than 1225 chocolate chips? (d) what is the percentile rank of a bag that contains 1425 chocolate chips?

Answers: 1

Answer

Mathematics, 21.06.2019 18:00

Determine the difference: 3.2 × 1010 – 1.1 × 1010. write your answer in scientific notation.

Answers: 1

Answer

Mathematics, 21.06.2019 22:00

What is the solution to the division problem below x3+x2-11x+4/x+4

Answers: 2

Answer

You know the right answer?

An automobile manufacturer has given its jeep a 51.3 miles/gallon (MPG) rating. An independent testi...