Stephanie Robbins is the Three Hills power Company management analyst assigned to simulate maintenance costs. In section 15.7 we describe the simulation of 15 generator breakdowns and the repair times required when one repairperson is on duty per shift. The total simulated maintenance cost of the current system is $4,320.

Robbins would now like to examine the relative cost-effectiveness of adding one more worker per shift. The new repairperson would be paid $30 per breakdown hour is still $75. Robbins makes one vital assumption as she begins--that repair times required with only one repairperson on duty per shift. Table 15.14 can then be restated as follows:

Repair Time required(Hours) Probability

½ 0.28

1 0.52

1 ½ 0.20

1.00

a. simulate this proposed maintenance system change over a 15-generator breakdown period. Select the random numbers needed for times between breakdowns from the second-from-the-bottom row of table 15.5. (Beginning with the digits 69). Select random numbers for generator repairs times from the last row of the table (beginning with 37)

b. should three hills add a second repairperson each shift.