1)

A researcher wants to estimate the proportion of women over age 55 who are widows.

She wishes to be 90% confident that her estimate is within 5% of the true proportion.

If no estimate of the sample proportion is available, how large should the sample be?

2)

Assume that the mean systolic blood pressure of adults is 120 mm of mercury (Hg),

and the population standard deviation is 5.6 mm of Hg. If a sample of 100 adults is

randomly selected from this population, what is the probability that the average

systolic blood pressure for the sample will be more than 120.952 mm of Hg?

3)

A sample of 16 history exam scores produced a sample mean of 68 points and a

sample standard deviation of 9 points. Find the 99% confidence interval for the

population mean of the history exam scores?

4)

The growing seasons for a random sample of 35 U.S. cities were recorded, yielding

a sample mean of 190.7 days. If the population standard deviation is 54.2 days. Find

the 95% confidence interval of the true mean?

5)

If 24% of middle aged men have undiagnosed sleep apnea, and a random sample of

800 middle aged men are tested, what is the probability that more than 210 men

will be found to have previously undiagnosed sleep apnea?

Hint: Use the normal approximation to the binomial distributio