A Medical Devices Company Wants to Know the Number of Hours

Multiple Choice

A medical devices company wants to know the number of hours its MRI machines are used per day. A previous study found a standard deviation of four hours. How many MRI machines must the company find data for in order to have a margin of error of at most 0.5 hour when calculating a 98% confidence interval?

A) 346.26
B) 347
C) 424.69
D) 425