Problem 7-7 A worker-machine operation was found to involve 3.6 minutes of machi
ID: 2746482 • Letter: P
Question
Problem 7-7
A worker-machine operation was found to involve 3.6 minutes of machine time per cycle in the course of 40 cycles of stopwatch study. The worker’s time averaged 2.0 minutes per cycle, and the worker was given a rating of 120 percent (machine rating is 100 percent). Midway through the study, the worker took a 10-minute rest break. Assuming an allowance factor of 17 percent of work time which is applied only to the worker element (not the machine element), determine the standard time for this job. (Do not round intermediate calculations. Round your final answer to 2 decimal places.)
rev: 02_05_2015_QC_CS-1706, 06_13_2015_QC_CS-17
A worker-machine operation was found to involve 3.6 minutes of machine time per cycle in the course of 40 cycles of stopwatch study. The worker’s time averaged 2.0 minutes per cycle, and the worker was given a rating of 120 percent (machine rating is 100 percent). Midway through the study, the worker took a 10-minute rest break. Assuming an allowance factor of 17 percent of work time which is applied only to the worker element (not the machine element), determine the standard time for this job. (Do not round intermediate calculations. Round your final answer to 2 decimal places.)
Explanation / Answer
Machine Run Rate per cycle: 3.6 mins
Worker Run Rate per cycle: 2 mins
Efficiency of Worker: 120%
Efficiency of Machine: 100%
Utilization of Machine: 100 %
Utilization of Worker: 100-17= 83%
Actual Run Time = Standard Run Time / (Efficiency * Utilization)
A-Standard Time for Machine per cycle = (Run Time * Efficiency*Utilization
= (3.6 * 100%* 100%)
= 3.6 minutes
B-Standard Time for Worker per cycle = Run Time * Efficiency * Utilization
= 2 * 120% * 83%
= 1.992 minutes
Therefore Standard Run Time for the Job = A + B
=3.6 + 1.992 = 5.592 minutes
Answer : Standard Run Time for the Job including Machine and Worker is approx. 5.592 minutes