Posted by **katie** on Tuesday, April 3, 2012 at 8:31am.

A researcher wishes to estimate the mean weekly wage of the several hundreds of workers employed

by a certain firm within plus or minus 20USD and with a 99% degree of confidence. From past

experience, the researcher knows that the weekly wages of these employees are normally distributed

with a standard deviation of 40USD. What is the minimum sample size required? [