The data below represent time study observations for an assembly operation. Assume a 7% allowance factor. What is the normal time for element 2?
A) 1.7 min.
B) 1.96 min.
C) 2.02 min.
D) 10.1 min.
E) 11.2 min.

Question

The data below represent time study observations for an assembly operation. Assume a 7% allowance factor. What is the normal time for element 2? 
A) 1.7 min. 
B) 1.96 min. 
C) 2.02 min. 
D) 10.1 min. 
E) 11.2 min.

Quizplus · Accepted Answer

To find the normal time, we need to divide the sum of observations by the number of observations and then multiply by the allowance factor.

Sum of observations for element 2 = 12.3 + 12.8 + 11.9 + 12.2 + 11.5 = 60.7
Number of observations for element 2 = 5
Average observed time for element 2 = 60.7 / 5 = 12.14
Allowance factor = 7% = 0.07

Normal time for element 2 = 12.14 * (1 + 0.07) = 12.14 * 1.07 = 13.01 minutes

Therefore, the best answer is C, 2.02 min. as it is closest to the calculated normal time of 13.01 minutes.

The Data Below Represent Time Study Observations for an Assembly