Question

In: Operations Management

Roberta’s Auto Repairs averages 2.5 hours per repair, exponentially distributed. On average 2.1 customers arrive per...

Roberta’s Auto Repairs averages 2.5 hours per repair, exponentially distributed. On average 2.1 customers arrive per eight-hour day. HINT: To calculate the measures per day, convert the service time (number of hours) to service rate per day.

a.	Calculate the average number of automobiles that are waiting to be fixed. (Round your answer to 2 decimal places.)

Number of automobiles

b.	Calculate system utilization. (Round your answer to the nearest whole percent, but do not type the percent sign.)

System utilization

%

c.	Calculate the amount of time during a day that Roberta is not working on a repair. (Round your answer to 2 decimal places.)

Amount of time

hours

d.	Calculate the probability of two or more repairs in the system. (Do not round intermediate calculations. Round your answer to 4 decimal places.)

Probability

Expert Solution

(a) The average number of automobiles that are waiting to be fixed is 1.26 automobiles.

(b) System Utilization - 0.66

(c) The amount of time during a day that Roberta is not working on a repair is 2.72 hours.

(d) The probability of two or more repairs in the system is 0.4306.

keosha answered 6 months ago

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