Given the following information, determine the sample size needed if the standard time estimate is to be within 5 percent of the true mean 99 percent of the time.
Work Element
Standard Deviation (minutes)
Mean Observed Time (minutes)
1
0.20
1.10
2
0.10
0.80
3
0.15
0.90
4
0.10
1.00
(Round your answer to the nearest whole number, the tolerance is +/-1.)