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

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.)

Transcribed Image Text:

OBSERVATIONS (MINUTES) ELEMENT Prepare daily reports Photocopy results 1 2 3 4 5 35 40 33 42 39 PERFORMANCE RATING (%) 120 12 10 36 15 13 110 5 5 90 15 18 21 17 45b 85 Label and package reports 3 3 Distribute reports 934 Photocopying machine broken; included as delay in the allowance factor. Power outage; included as delay in the allowance factor.