# Question: There is concern about the speed of automobiles traveling over

There is concern about the speed of automobiles traveling over a particular stretch of highway. For a random sample of 28 automobiles, radar indicated the following speeds, in miles per hour:

a. Check for evidence of nonnormality.

b. Find a point estimate of the population mean that is unbiased and efficient.

c. Use an unbiased estimation procedure to find a point estimate of the variance of the sample mean.

a. Check for evidence of nonnormality.

b. Find a point estimate of the population mean that is unbiased and efficient.

c. Use an unbiased estimation procedure to find a point estimate of the variance of the sample mean.

## Answer to relevant Questions

Assume a normal distribution with known population variance. Calculate the margin of error to estimate the population mean, m, for the following. a. 98% confidence level; n = 64; σ2 = 144 b. 99% confidence level; n = 120; ...Assume a normal distribution with known population variance. Calculate the width to estimate the population mean, m, for the following. a. 90% confidence level; n = 100; σ2 = 169 b. 95% confidence level; n = 120; σ = 25 Calculate the margin of error to estimate the population mean for each of the following. a. 99% confidence level; x1 = 25; x2 = 30; x3 = 33; x4 = 21 b. 90% confidence level; x1 = 15; x2 = 17; x3 = 13; x4 = 11; x5 = 14 How much do students pay, on the average, for textbooks during the first semester of college? From a random sample of 400 students the mean cost was found to be $357.75, and the sample standard deviation was $37.89. Assuming ...Suppose that a random sample of 142 graduate-admissions personnel was asked what role scores on standardized tests (such as the GMAT or GRE) play in the consideration of a candidate for graduate school. Of these sample ...Post your question