# Lean & Sustainable Operations

I need help with a Management question. All explanations and answers will be used to help me learn.

1. A manufacturer subjected 100 machines to 6000 hours of testing. One machine failed at 2340 hours, another one failed at 4100 hours and a third one failed at 100 hrs.

a) What is the % failure rate?
b) Number of failures per unit-hour and MTBF?
c) If 250 such machines are deployed, how many are expected to fail in one year?

2. Use the data as given in Problem #6 (page 198) of your textbook to calculate following:

a) Rate efficiency

b) Speed Efficiency

c) Performance efficiency

3. A system consists of the following four elements. Reliability of the elements are: R1= 0.95, R2=0.85, R3=0.92 Calculate the overall reliability of the system.

# Lean & Sustainable Operations

I need help with a Management question. All explanations and answers will be used to help me learn.

1. A manufacturer subjected 100 machines to 6000 hours of testing. One machine failed at 2340 hours, another one failed at 4100 hours and a third one failed at 100 hrs.

a) What is the % failure rate?
b) Number of failures per unit-hour and MTBF?
c) If 250 such machines are deployed, how many are expected to fail in one year?

2. Use the data as given in Problem #6 (page 198) of your textbook to calculate following:

a) Rate efficiency

b) Speed Efficiency

c) Performance efficiency

3. A system consists of the following four elements. Reliability of the elements are: R1= 0.95, R2=0.85, R3=0.92 Calculate the overall reliability of the system.