Albert Abbasi, VP of Operations at Ingleside International Bank, is evaluating the service level provided to walk-in customers.Accordingly, he plans a sample of waiting times for walk-in customers.If the population of waiting times has a mean of 15 minutes and a standard deviation of 4 minutes, the probability that Albert's sample of 64 will have a mean between 16.5 and 18.5 minutes is ___.
A)0.1865
B)0.2667
C)0.7333
D)0.5468
E)1.0000

Question

Quizplus · Accepted Answer

The sample mean follows a normal distribution with mean 15 and standard deviation 0.5 (4/sqrt(64)). The probability of the sample mean being between 16.5 and 18.5 can be found using the standard normal distribution, resulting in approximately 0.1865.

Albert Abbasi, VP of Operations at Ingleside International Bank, Is