Question: A national beauty chain wants to estimate the number of times a year a woman has her hair done at a beauty salon if she uses one at least once a year. The chains researcher estimates that, of those women who use a beauty saloon at least once a year, the standard deviation of number of times of usage is approximately 6. The national chain wants the estimate to be within one time of the actual mean value. How large a sample should the researcher take to obtain a 98% confidence level?