A local fraternity is deciding between three different refrigerators. The refrigerators have a mean time between failure and mean time to repair as shown in the table. MTBF MTTR
Refrigerator A 50 hours 2 hours
Refrigerator B 125 hours 3 hours
Refrigerator C 200 hours 4 hours
What refrigerator(s) will provide the greatest availability?
A) Refrigerator A
B) Refrigerator B
C) Refrigerator C
D) Refrigerator A and Refrigerator B
E) Refrigerator A and Refrigerator C

Question

Quizplus · Accepted Answer

The formula for availability is MTBF/(MTBF + MTTR). 
For Refrigerator A: 
Availability = 50/(50+2) = 0.961

For Refrigerator B: 
Availability = 125/(125+3) = 0.976

For Refrigerator C: 
Availability = 200/(200+4) = 0.980

Refrigerator C has the highest availability of the three options, making it the best choice.

A Local Fraternity Is Deciding Between Three Different Refrigerators