The snapback timing method was used in a direct time study of task includes a machine cycle. Elements a, b, c, and d are performed by the operator and element m is a machine semiautomatic cycle. Element b is an internal element performed simultaneously with element m. Element d is an irregular element performed every 12 cycles. A_pfd = 0.1. A_m = 0.15

Work element _____ a b c d __

Observed time, manual, 0.34 0.75 0.55 0.65

Performance rating 110% 90% 95% 100%

Machine element m

Observed time, machine (idle) 1.5 (idle) (idle)

Select correct answer from below.

1. 1.045

2. 1.725

3. 2.77 min

4. 2.45 min