How to ask questions in case interview

Case Interview
New answer on Jul 16, 2020
7 Answers
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Anonymous A asked on Feb 10, 2020

Dear all, I would like to seek for advice on how to ask "good questions" during interview. Sometimes interviewers' will ask me questions like "what do you think", so I believe it's some questions are too "general". Here is my questions:

1. Is it okay to ask during the clarification part: (1) Is this internal or external problem? (2) Is this a cost issue or revenue issue?

2. Today I did a case discussing about why visitors to a church has been dropping. I used an "external-internal" issue tree to solve the case, and eventually found out that the wedding event taking place is reducing, which is causing the problem. At this point, how should I proceed the case? Can I simply ask "WHY" is the wedding events reducing? Or I should at least brainstorm several possibilities, and ask which one is correct? Or, I should have another structure to discuss the possible internal / external issue that is causing a drop in wedding events?

3. Following the above case, the answer was males have been reducing - due to a war. Again, how should I ask the question to explore the reason that males have been reducing? It's nearly impossible to think of this reason...

Thank you so much.

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Anonymous replied on Feb 11, 2020

Hi A,

the whole objective of every case is to find the root causing issue, isolate it and provide recommendations to fix it.

So regarding your questions:

I. be more specific about your questions and work with hypotheses:

(1) i.e. is this a company internal problem or this is through changing environmental environment (i.e. market crisis, regulatory, political change, etc.) - do you have any data on that?

(2) provide the options for decreasing profitability: (a) inreasing costs, flat revenues (b) decreasing revenues flat costs (c) increasing revenues and overincreasing costs and (d) decreasing costs and overdecreasing revenues - to test these scenarios, ask for data

II. If your structure is MECE no matter which frameworks you combine and use it covers all the aspects (incl. political, societal and demographics). In your case you could also bring a substructure to answer the question what are the drivers of # of weddings? Again work with hypotheses to answer the question, why the # of weddings is dropping until you find the right answer

III. Examples of the questions might be:

-what is the proportion of males and females throught different age groups in this society / place? - Here you should already get a hint about mismatch between males and females in the specific age group

-Are there any specific reasons for the disproportion in this age group?

-You would probably asked to brainstorm about the reasons at this point to assess your creativity of answers - it's always good to brainstorm with some initial structure and not simply out of the blue

I hope it helps you.

Good luck!


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Content Creator
updated an answer on Feb 11, 2020
#1 Coach for Sessions (4.000+) | 1.500+ 5-Star Reviews | Proven Success (➡ | Ex BCG | 9Y+ Coaching

Hi Anonymous,

please find the answers below:

  1. These questions are too generic and give the impression you want the interviewer to solve the problem for you – I would not recommend to ask them at the beginning
  2. You should never simply ask why (this is actually something the interviewer probably will ask you); you should also not start brainstorming immediately. Instead you should define a structure and then start brainstorming.
  3. Again, you should not simply ask questions, but define a structure and then brainstorm. Using the structure of internal and external, for example, the fact that males are not attending could be included under one of the components of external reasons (“competing” offer, that is, the war in this case)



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Content Creator
replied on Feb 11, 2020
MBB | 100% personal interview success rate (8/8) and 95% candidate success rate | Personalized interview prep

#1 Rule: Ask questions that help YOU understand the world.

If you're confused, figure out why and ask the question that clarifies (normally this is around how the business actually operates, or the real challenge they're facing).

Forget about the classic questions. Think for yourself and actually drive your case. Imagine yourself at the client site, with your team, in front of a whiteboard, figuring out the answer. Too often, candidates have a pocket list of 10 questions that they're seen/heard over and over again, and they repear them without actually understanding why they're asking them in the first palce.

In regards to your questions:

1. This is so generic. Add color to this. I.e. for External vs. Internal "I'm thinking this could be due to something going on inside the company (maybe operational issues, change of management, something like that) or something outside of our control such as price shocks, new competitors coming in, or a generally declining demand. Do we have any information on this?"

2. Your job is to figure out why. Your framework doesn't end after the initial prompt + clarifying questions. You need to continue to use frameworks and strucutred thoughts throughout the case. DRIVE to the answer by using a structured approach. What could be causing this and what information do you need to figure out the why? In short, yes, come up with another structure (external vs internal could work)

3. You just need to have a structure that covers this. If you've taken a MECE approach, this would be covered. For example, if you did external vs. internal, in your external segment it's not unreasonable that you would put: Competing products taking their interest away, emigration, conflict/political issues, etc.

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Content Creator
replied on Feb 10, 2020
McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School


1) I would rather ask: Is it that our Revenues have increased, costs have decreased or both? Don't ask if it is an external problem, rather make a good structure and go through the structure

2) When you dig deeper into the problem - you can always ask first: "Do we know why that happened?". If the interviewer tells you "We need to explore", you draw a new structure to dig deeper

3) It's not about you guessing the reason. And even if you guess - it will not be counted as a correct answer. It's about you having a structure in place to dig deeper (e.g. a list of drivers influencing marriage rates)


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Content Creator
replied on Jul 16, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut


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Content Creator
replied on Mar 01, 2020
McKinsey | MBA professor for consulting interviews

I recommend to make more specific questions or to proactively ask it, by giving an example of your solution, without leaving the interviewer the impression you want her solution (e.g. instead of asking for the cost breakdown of the client, you can say something like: the most important cost items for the client should be ... do we have to consider other? do we have any data about these?)

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Content Creator
replied on Feb 29, 2020
BCG |NASA | SDA Bocconi & Cattolica partner | GMAT expert 780/800 score | 200+ students coached


Before making a general question and asking "why?", is a good habit to do a little brainstorming and come up with somne potential answers. Of course you can not think of a war, but after seein you proposing good alternatives, the interviewer will be happy to share with you the right information.


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