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Operations Cases? McK

Case McKinsey Mckinsey operations operations
New answer on Nov 10, 2023
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Anonymous B asked on Dec 11, 2017

I had a recent first round and had two very specific operations Cases, both having to calculate OEE. I've practiced every other case type and even though I passed this round, these through me for a loop as structuring and ideas were on the micro level very different then many of the other cases I've done.

Anyone have any resources for practicing these specific case types?


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updated an answer on Dec 11, 2017
McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School


There are several types of operational cases that you may have:

1) Operational math problems. (e.g. Should we increase the speed of the elevator or just buy a second one? How should we reduce the queues? How should we increase the output of a factory?).


  • Usually, you have to look at the process. Even the most complicated systems have the inflows and outflows

The key concepts that you have to learn:

  • Capacity and utilization (both machine and people)
  • Cycle time, Throughput time, Little's Law
  • How the does lowest cycle time influence the production? (Lead time = cycle time of the slowest process)
  • How can we mitigate the bottlenecks with low cycle time? (Buffer, Parallel process, speeding up)

2) Cost cutting cases


  • What is the cost composition and what are the biggest costs
  • Benchmarking of the biggest costs to find the improvement potential
  • Process improvements to meet the benchmarks
  • Costs and benefits of the proposed initiatives

The key concepts that you have to learn:

  • Internal / external benchmarking
  • Idle time
  • Core processes (usually are optimized) and the supporting processes (usually are cut)
  • Math structures (Frequency of operations * time per operation)
  • Other useful structures (e.g. people - process - technology)

Feel free to reach me for further help with these cases.



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Elie on Apr 28, 2018

Hello Vlad, I'd like to know where does demand fit in the 1st case of your framework. Thank you


Originally answered question:

Mckinsey operations case types

Content Creator
replied on Sep 12, 2016
Ex-McKinsey Engagement Manager and IESE MBA

Hi! Here an OPS Associate at Mckinsey

I had 3 + 3 interviews and only one was really about operations.

It was about calculating the OEE of a manufacturing plant. However, there is no need to have specific knowledge since you will receive the instructions in case you dont know how to calculate it.

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Content Creator
replied on Nov 10, 2023
ex Jr. Partner McKinsey |Senior Interviewer| Real Feedback & Free Homework between sessions|Harvard Coach|10+ Experience

YES! Ping me a DM for some real case examples. Warm regards, Frederic

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Odeh replied on Dec 12, 2017

Can you please clarify what OEE is? Acronyms can mean different things to different people. Thanks.

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Anonymous on Dec 12, 2017

OEE is Overall Equipment Effectiveness...a calculation used to weight scheduled machine time vs effective machine time

Originally answered question:

Mckinsey operations case types

Anonymous replied on Sep 09, 2016

It's not very different from hiring for a regular general track McKinsey hire. You'll have cases and the areas can vary widely - sure, you might get an odd ops case, but if you do really well in them, they'll quickly challenge you with non-ops cases.

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Vlad gave the best answer


McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School
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