A Methods and Measurement Analyst Wants to Develop a Time

Multiple Choice

A methods and measurement analyst wants to develop a time standard for a certain task. In a preliminary study, he observed one worker perform the task six times with an average observed time of 20 seconds and a standard deviation of 2 seconds.
How many observations should be made if he wants to be 95.44 percent confident that the maximum error in the observed time is 1 second?

A) 3
B) 4
C) 13.3
D) 16
E) 25