Answer:
hello your question lacks some details below is the complete question
A bank of 10 machines requires regular periodic service. Machine running time and service time are both exponential. Machines run for an average of 44 minutes between service requirements, and service time averages six minutes per machine
If operators cost $15 per hour in wages and fringe benefits and machine downtime costs $75 per hour in lost production, what is the optimal number of operators for this bank of machines?
A 1
B 2
C 3
D 4
E 5
Answer : 3 operators ( c )
Explanation:
number of machines = 10
machine run time for each = 44 minutes
service time = 6 minutes
cost of each operator = $15 per hour
loss during machine down time = $75 per hour
hence the optimal number of operators
The total minutes the machine would work in a hour
= (60 - 6) * 10 = 540 minutes
assuming we assign 180 minutes to each operator then each operator would cost = 15 * 3 = $45
for three operators that would be = 45 * 3 = $135
lost inquired during down time
= 6 minutes * 10 = 60 minutes i.e the total cost inquired per hour = $75
hence 3 operators would be an optimal number of operators because the operators would work lesser hours and more efficiently as well