A time study analyst has collected some preliminary data on a delivery job, with an average time to do the delivery job of 15.5 minutes with a standard deviation of 2.5 minutes. If we use an alpha value of 4%, and we want our final estimate to be within 0.25 minutes of the true value, how large a sample should be taken?

Question 14 options:

n = 500 observations

n = 127 observations

n = 1,035 observations

n = 422 observations