A random sample of 187 full-grown lobsters had a mean weight of 19 ounces and a population standard deviation of 3.3 ounces. Construct a 98% confidence interval for the population mean μ.

How many women must be randomly selected to estimate the mean weight of women in one age group. We want 90% confidence that the sample mean is within 3.4 lb of the population mean, and the population standard deviation is known to be 25 lb.

A sample of size 39 will be drawn from a population with mean 15 and standard deviation 6. Find the probability that  will be greater than 16.

A survey reported that in a recent year, the mean serum cholesterol level in milligrams per deciliter for U.S. adults was 203 with a standard deviation of 39. A random sample of 102 adults was chosen. What is the probability that the mean cholesterol level is between 199 and 208?

A survey reported that in a recent year, the mean serum cholesterol level in milligrams per deciliter for U.S. adults was 204 with a standard deviation of 37. A random sample of 116 adults was chosen. Find the 33rd percentile of the sample mean.