An 8 hours work measurement study in a plant reveals the following : Units produced= 320 nos. Idle time = 15% performance rating-= 120% . allowances = 12% of normal time. Determine the standard time per unit produced.
Solution
Observed time for 320 unit s= working time - idle time
= 8-8-X0.15= 8-1.2
= 6.8 hours
= 6.8X 60 = 480 minutes.
Observed time per unit = 408/320 = 1.275 minutes.
Normal time per unit = Observed time / Unit X observed rating / standard rating
= observed time / unit X performance rating
= 1.275X 120/ 100
= 1.53 minutes.
Standard time/ unit = Normal time/ Unit+ Allowances
= 1.53 Minutes + 12% of 1.53 minutes
= 1.53 + 1.2 /100 X 1.53
= ( 1.53 + 0.184) minutes
= 1.714 minutes