Suppose It Is Desired to Estimate the Average Time a Customer

Multiple Choice

Suppose it is desired to estimate the average time a customer spends in a particular store to within 5 minutes $$( \text { e.g. } \pm 5 \text { minutes) }$$ at 99% reliability. It is estimated that the standard deviation of the
Times is 15 minutes. How large a sample should be taken to get the desired interval?

A) n = 299
B) n = 60
C) n = 25
D) n = 35