APICS CPIM-8.0 Exam - Topic 1 Question 9 Discussion

Actual exam question for APICS's CPIM-8.0 exam

Question #: 9
Topic #: 1

If the total part failure rate of a machine is 0.00055 failures per hour, what would be the mean time between failures (MTBF) in hours?

A1,818.2

B59.99945

C1.98

D0.99945

Show Suggested Answer

Suggested Answer: A

The mean time between failures (MTBF) is the inverse of the failure rate. The failure rate is given as 0.00055 failures per hour, so the MTBF is 1/0.00055 = 1,818.2 hours. This means that the average time the machine operates without failing is 1,818.2 hours. Reference: MTBF Formula | How to Calculate Mean Time Between Failure? - EDUCBA, Mean time between failures - Wikipedia

by Evangelina at May 04, 2025, 04:53 AM

Limited Time Offer

25%

Off

Get Premium CPIM-8.0 Questions as Interactive Web-Based Practice Test or PDF

Contribute your Thoughts:

Submit Cancel

Dulce

6 months ago

Totally agree with A, solid math there!

upvoted 0 times

...

Yvette

7 months ago

Definitely A, that makes sense!

upvoted 0 times

...

Josefa

7 months ago

MTBF is calculated as 1 divided by the failure rate.

upvoted 0 times

...

Troy

7 months ago

Are we sure about that? Feels off to me.

upvoted 0 times

...

Rueben

7 months ago

Wait, 1,818.2 hours? That seems way too high.

upvoted 0 times

...

Bernardine

7 months ago

I think the correct answer is A, but I’m not completely confident. I need to double-check my math!

upvoted 0 times

...

Lilli

8 months ago

I feel like the answer should be a larger number since it's MTBF, but I’m second-guessing my calculations.

upvoted 0 times

...

Emogene

8 months ago

I think I practiced a similar question where we had to find MTBF from a failure rate. I’ll try to remember the formula!

upvoted 0 times

...

Art

8 months ago

I remember MTBF is the inverse of the failure rate, but I’m not sure how to calculate it exactly.

upvoted 0 times

...

Kimberely

8 months ago

I think I've got it - the MTBF is just the reciprocal of the failure rate, so the answer should be 1/0.00055.

upvoted 0 times

...

Alyssa

9 months ago

Wait, is the failure rate given per hour or per some other time period? I need to make sure I'm using the right units.

upvoted 0 times

...

Raymon

9 months ago

Okay, I know the MTBF is the inverse of the failure rate, so this should be a simple division problem.

upvoted 0 times

...

Quentin

9 months ago

Hmm, I'm a bit unsure about the formula to use here. Let me think this through step-by-step.

upvoted 0 times

...

Allene

9 months ago

This looks like a straightforward calculation, I should be able to handle this.

upvoted 0 times

...

Antonio

1 year ago

A) 1,818.2 hours? Wow, that machine must be built like a tank! I wonder if they use it to power a small country or something. Either way, it's got to be the answer.

upvoted 0 times

Ernest

11 months ago

D) 0.99945

upvoted 0 times

...

Patti

11 months ago

C) 1.98

upvoted 0 times

...

Lottie

12 months ago

B) 59.99945

upvoted 0 times

...

Pok

12 months ago

A) 1,818.2 hours? Wow, that machine must be built like a tank! I wonder if they use it to power a small country or something. Either way, it's got to be the answer.

upvoted 0 times

...

Leandro

1 year ago

I agree with Terry, A) 1,818.2 makes sense based on the formula

upvoted 0 times

...

Goldie

1 year ago

C) 1.98 hours? Really? That can't be right. I'd be surprised if the machine lasted that long without having a meltdown. Time to go back to the drawing board on this one.

upvoted 0 times

Theola

12 months ago

B) 59.99945 could also be a possible MTBF value for the machine.

upvoted 0 times

...

Zana

12 months ago

A) 1,818.2 seems more reasonable for the MTBF of the machine.

upvoted 0 times

...

Shanda

12 months ago

C) I agree, 1.98 hours seems too short for the mean time between failures.

upvoted 0 times

...

Leatha

12 months ago

D) 0.99945

upvoted 0 times

...

Roosevelt

12 months ago

C) 1.98

upvoted 0 times

...

Quentin

12 months ago

B) 59.99945

upvoted 0 times

...

Raina

1 year ago

A) 1,818.2

upvoted 0 times

...

Terry

1 year ago

But the MTBF is calculated as 1 divided by the failure rate, so it should be A)

upvoted 0 times

...

Blythe

1 year ago

Hmm, D) 0.99945 is a bit too low, don't you think? I bet the machines would be breaking down every hour if that were the case. Better go with something more reasonable.

upvoted 0 times