A Bank Manager Wants to Determine the Percent of Time

Multiple Choice

A bank manager wants to determine the percent of time the bank's tellers are working and idle. He decides to use work sampling, and his initial estimate is that the tellers are idle 22% of the time. Approximately how many observations should be taken to be 95% confident that the results will not be more than 5% away from the true result?

A) 6
B) 16
C) 203
D) 264
E) 246