Based on a careful work study in the Hofstetter Corp., the results shown in the following table have been observed:

ELEMENT OBSERVATIONS

(MINUTES) PERFORMANCE 1 2 3 4 5 RATING (%)

Prepare daily reports 35 40 33 42 39 120 Photocopy results 12 10 36a 15 13 110 Label and package reports 3 3 5 5 4 90 Distribute reports 15 18 21 17 45b 85 a

Photocopying machine broken; included as delay in the allowance factor.

b Power outage; included as delay in the allowance factor.

a) Compute the normal time for each work element.

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

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