Question

How many work cycles should be timed to estimate the average cycle time to within 2 percent of the sample mean with a confidence of 99.0 percent if a pilot study yielded these times (minutes): 5.2, 5.5, 6.6, 5.3, 5.5, and 5.1? The standard deviation is 0.547 minutes per cycle. (Use the "mean time" value to 2 decimal places and other values to 3 decimal places for intermediate calculations. Round up your final answer to the next whole number.)