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Questions regarding first interview for internship?

Dresscode interview prep
New answer on Feb 05, 2020
5 Answers
1.7 k Views
Andrew asked on Feb 03, 2020

I am just a Sophmore so I was suprised I heard back from local firm about an internship for the summer. I'm super green, and feel a little out of my league, but I want to try my best to get it. They must have liked something about me!

What should I wear to the interview?

What type of questions should I expect?

Generally, how conservative are consulting firms? I have been growing my hair out to my shoulders, but should I get it cut?

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Best answer
replied on Feb 04, 2020
McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School


I recommend the following approach:

1) Start with "Case in point" book - you can download this book for free everywhere. It's not the best guide on how you should approach the cases, however, it will give you the basic understanding.

2) Start practicing cases with partners here or find them locally. !!! Find experienced partners or coaches who can provide a good feedback!!!

3) Purchase and read Viktor Cheng Book (Amazon Kindle store) and listen to LOMS (his website). I recommend to reread the book and listen to LOMS every 15 cases. Every time, having more experience, you’ll be finding something new.

4) Practice fast math

  • Learn how to multiply double digit numbers (
  • Learn the division table up to 1/11 (i.e. 5/6 = 83.3)
  • Learn how to work with zeros (Hint: 4000000 = 4*10ˆ6)
  • Use math tools (Mimir math for iOS), Math tool on Viktor Cheng website to practice

5) Below you can find a list of the most common case types and some high-level recommendations on structuring:

  • Market sizing - structuring from the supply or demand side. Structuring using a formula or using an issue tree
  • Profitability - basic profitability framework. Remember about different revenue streams and product mix
  • Market context cases (Market Entry, New product, Acquisition, etc). Always start with the big picture "market". Finish with something specific to the case (e.g. How to enter?"). Structure it as if you are defining the work streams for the real project.
  • Operational math problem (e.g. Should we increase the speed of an elevator or just buy a second one? How should we reduce the queues? Etc.) - Structuring as a process / value chain, with inflows, operations, and outflows
  • Cost cutting - I provided the recommendations on structuring it here:
  • Valuation - Purely financial structure with cash flows, growth rate, WACC / hurdle rate, etc.
  • Synergies - revenue synergies (price, qty, mix) and cost synergies (value chain).
  • Social / economics cases (e.g. How to improve the quality of life in the city? How to increase the revenues of the museum?) - huge variability. Practice 3-5 social cases before the interview

6) Also, I would try to focus on the most common industries in the following priority(sorted by probability of getting a case): 1-retail and CPG; 2-airlines; 3-Telecom; 4-banking; 5-natural resources; 6-tech

7) ! Important: don't forget about the FIT interview part. Crafting you stories and backups stories will require a couple of weeks!


Here is a good list of articles regarding the different parts of the case:

1) Start with clarifying questions:

2) Communicating while structuring. Here is a long post by me on how to communicate the structure during the case study:

3) Using hypothesis. I made a post about hypothesis here:

4) Communicating while making calculations:

  • Always tell the interviewer your approach
  • Check with the interviewer that your approach is correct
  • Come to the interviewer with some preliminary answers
  • Check your assumptions with the interviewer

5) Communicating during the analysis of graphs / tables

  • Take a minute to look at the graph. Read the graph title. Look at the graph type and define the type (pie chart, line chart, etc). Look at the legend (ask for clarifying questions if necessary). Identify whats going on on the graph. Look for: Trends, % structures. Look for unusual things - correlations, outliers,
  • Make 3-4 conclusions from the graph. Think out loud on potential hypothesis on what could be the root cause / what are the consequences
  • Prioritize the most important for your current analysis and move forward with the case

6) Communicating while having questions on creativity

  • Ask an interview for a minute to think
  • Think of several buckets of ideas (e.g. organic growth / non-organic growth / differentiation). Remember to think as big as possible
  • Narrow down to each bucket and generate as many ideas as possible
  • Present the structure (buckets) and then your ideas

7) Communicating your conclusion. You can find a good example I've posted here:

8) Communicating your FIT stories

Use the top-down approach while communicating your stories. "The Pyramid Principle" is the must-read by ex McKinsey on this topic.

I recommend using the STAR framework:

  • In Situation, you should briefly provide the context, usually in 1 or 2 sentences
  • Task usually includes 2 or 3 sentences describing the problem and your objective.
  • Then you provide a list of specific actions you took to achieve the goal. It should take 1 or 2 sentences per action (Usually 3-4 actions). Note that the interviewer can stop you any minute and ask for more details.
  • The results part should have 1 or 2 sentences describing the outcomes. This part is finalizing your story - make sure it can impress the interviewer and stay in the memory.


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Content Creator
replied on Feb 05, 2020
McKinsey | NASA | top 10 FT MBA professor for consulting interviews | 6+ years of coaching

I suggest to read the Cosentino's Case in point and then practice 40+ mock cases with other candidates to master the case resolution.

The interview will be structured in 3 parts:
- Personal Experience Interview: fit and CV questions to assess your personal impact, leadership skills, and entrepreneurial spirit
- Case Interview: typical business case to evaluate your structure in approaching problems, problem-solving skills, and business sense
- Your final questions to the interviewers


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Content Creator
replied on Feb 05, 2020
BCG |NASA | SDA Bocconi & Cattolica partner | GMAT expert 780/800 score | 200+ students coached

Hello Andrew,

It depends on the country and office's culture but I would stongly recommend to wear a suit and a tie. Regarding the hair, let's say that there are not written rules but you have to look professional and not to be noticed.

Regarding the "questions", it will be a business case interview with an opening Fit interview.


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Content Creator
replied on Feb 04, 2020
#1 Coach for Sessions (4.500+) | 1.500+ 5-Star Reviews | Proven Success (➡ | Ex BCG | 10Y+ Coaching

Hi Andrew,

suit (blue, gray) + tie are always the best dress code for man in consulting interviews.

Consulting firms tend to be formal – there may be differences in terms of the specific company you will interview with. In general I would recommend the following:

  1. Limit the amount of jewelry to watch and wedding band
  2. Avoid excessive cologne
  3. Standard shirts (white, French blue are always safe bets)
  4. Ordinary pen, bags, shoes, and other gadgets – no very peculiar staff
  5. Standard haircut if possible
  6. Standard tie (no cute symbols)

The standard interview in consulting covers the following:

  1. Fit questions. Eg Why consulting. More on that here:
  2. Case questions. Business case/market sizing – Eg Should our client merge with a competitor. More on that here:
  3. Your questions for the interviewer. More on that here:



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Andrew on Feb 04, 2020

Great, thank you. I’ll plan on a suit and tie. And I think I’ll breakdown and get cut my hair to something clean cut and tight. If I’m going into this field I’m gonna have to do it soon so it might as well be now. How intense do you think the case questions will be for an internship?

Francesco on Feb 04, 2020

Hi Andrew, the questions are normally the same as for full time, in some firms the interviewer may forgive some mistakes compared to a full time position though. Best, Francesco

Content Creator
replied on Feb 03, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut


Those questions totally depend on the firm, the role (e.g., is it client facing or is it more an analytics role in which you only work among peers, etc.)

Can you give more detail?



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Andrew on Feb 03, 2020

The internship description says we will be working in groups of teams with clients, so a little bit of both. But yes, interaction with clients.

Vlad gave the best answer


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