According to the AAA Foundation for Traffic Safety's American Driving Survey, U. S. drivers spend. on average, 51 minutes behind the wheel each day. A researcher believes this is an overstatement.

To investigate, a random sample of 75 drivers were selected. The study revealed that the mean

time behind the wheel for the sample of 75 drivers was 46.4 minutes with a standard deviation of

18.8 minutes. Is there convincing evidence that the mean time behind the wheel for all U. S. drivers

is less than 51 minutes? Use a = 0.01.

The pvalue of the test is 0.017 > 0.01, which means that there is not convincing evidence that the mean time behind the whell for all U.S drivers is less than 51 minutes.

Step-by-step explanation:

U.S. drivers spend on average, 51 minutes behind the wheel each day.

This means that at the null hypothesis we test that:

Is there convincing evidence that the mean time behind the wheel for all U.S. drivers is less than 51 minutes?

This means that the alternate hypothesis is:

The test statistic is:

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

51 is tested at the null hypothesis:

This means that

The study revealed that the mean time behind the wheel for the sample of 75 drivers was 46.4 minutes with a standard deviation of 18.8 minutes.

This means that

Value of the test-statistic:

Pvalue of the test:

The pvalue of the test is the probability of finding a sample mean less than 46.4, which is the pvalue of z when X = 46.4.

Looking at the z-table, z = -2.12 has a pvalue of 0.017.

Decision:

The pvalue of the test is 0.017 > 0.01, which means that there is not convincing evidence that the mean time behind the whell for all U.S drivers is less than 51 minutes.

step-by-step explanation:

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the figures below are made out of circles, semicircles, quarter … find the area and the perimeter of each figure and give your answers as a completely simplified exact value in terms of π (no approximations). remember that we'll also have to cut whatever areas we get in half, since we're only dealing im pretty sure that is the right answer

step-by-step explanation: