Based on a careful work study in the Richard Dulski Corp., the results shown in the following table have been observed: Observations (minutes) Performance Element 1 2 3 4 5 Rating (%) Prepare daily reports 35 40 33 42 39 120 Distribute reports Photocopy results Label and package reports 3 3 5 5 4 15 18 21 17 456 12 10 36 15 13 110 20820 90

a) Compute the normal time for each work element.

b) If the allowance for this type of work is 15%, what is the stan- dard time?

c) How many observations are needed for a 95% confidence level within 5% accuracy? (Hint: Calculate the sample size of each element.) ..