Schedule mock interviews on the Meeting Board, join the latest community discussions in our Consulting Q&A and find like-minded Interview Partners to connect and practice with!
Back to overview

Problem with Quant Questions

Hi,

While solving cases I noticed I was quite slow on the quant questions. I found this odd since math is my strong point. I suspect that I am not yet confident in driving the case in terms of finding what is quantitatively needed. Does the community have suggestions to help with my problem? Do I just need to practice more?

7
2.0k
12
Be the first to answer!
Nobody has responded to this question yet.
Top answer
Udayan
Coach
on Jun 29, 2020
Top rated Case & PEI coach/Multiple real offers/McKinsey EM in New York /12 years recruiting experience

Math in college is not the same as math when given in a case. The main difference being that case math requires understanding of context. This context is given in verbal form which you then have to interpret into an equation and solve accordingly. 

This is why the best way to practice these problems is to use a GMAT type of book. Maybe read aloud the questions to yourself and then answer them. Once you get better at these then move on to real cases to further improve.

All the best,

Udayan

Robert
Coach
on Jun 28, 2020
McKinsey offers w/o final round interviews - 100% risk-free - 10+ years MBB coaching experience - Multiple book author

Hi Anonymous,

I common issue which I see for many of my coachees: it's a huge difference wheter to do a 'simple' pure math question stand-alone vs. solving a math question integrated in a complex case situation.

While for the pure math question you only need to do the numbers and execute, usually you first need to develop a conceptual approach first for solving a math question integrated into the case.

As we all know (but sometimes don't want to accept), the human brain is not capable of multitasking, but merely switching between different tasks sequentially. So trying to do the conceptual work at the same time as the pure math usually leads to wasting time (in case you do calculation and only understand later that your conecptual approach is wrong) and is definitely more prone to errors (multi-tasking...).

So I'd try to really separate those two steps and firstly do the conceptual work and also communicate that approach explicity to your interviewer, before secondly just executing the numbers!

Hope this helps - if so, please be so kind and give it a thumbs-up with the green upvote button below!

Robert

on Jun 26, 2020

Hey! hope you're doing well and keeping safe. 

I found myself in a similar situation - I was fairly strong at math having aced all math courses in college/university but for some reason I seemed to struggle with case math. Here are some tips that worked for me:

- Case math, conceptually, is rather basic. Its arithmetic after all, however the arithmetic difficulty is dialed to 11! You're dealing with large numbers (millions and billions) AND you need to be quick! I would recommend using the math tool on victor cheng's case interview website and practicing daily to deal with large numbers and to get better at both estimaton and exact answers

-Practice in front of a friend/family member! I can't stress this enough. Doing math on your own vs doing it infront of somebody sitting across and staring at you is a different ball game. Create an interview like environment and practice the quant with somebody sat across from you. This will help greatly with confidence. Walk your interviewer through your formula, reason for using the formula (logic) and then involve them in the calculation. Explain any assumptions. Basically get more comfortable communicating.your thought process. 

Some other minor but helpful tips

-memorize your squares and cubes

-practice extensively with fractions, percentages (YouTube videos for shortcuts and drills)

Learn inverse numbers for e.g 1/6,2/6,3/6,4/6 1/7,2/7....1/8, for upto 11 - this will help improve your speed in mental math and consequently help you feel confident not to mention save time. 

For finding the driving factors in any case my advice would be to follow up any WHY question with a HOW MUCH question. So try and quantify any information you get and get to a level, by practice ofc, where you are constantly switching b/w qualitative and quantitative analysis and supporting one with the other. Practice as many live cases as you can. 

This is what worked for me, I am sure the experts would have much better advice. Hope this helps! 

5
Anonymous A
on Jun 26, 2020
I will definitely incorporate these tips, especially practicing in front of other people. Thank you so much for the advice!! I sincerely appreciate it :)
Deleted user
on Jun 27, 2020

Hello

You can try to practice on GMAT exercices

best

2
Anonymous A
on Jun 27, 2020
Will do, thanks!
Deleted
Coach
on Jun 30, 2020
FREE 1st session in November | From Lawyer to MBB | Top in FIT | 10x your structuring skills | Message to get Free Prep Checklist

Hi,

I also suggest that GMAT is a good idea!

Best,

Anton

Ian
Coach
edited on Jul 01, 2020
Top US BCG / MBB Coach - 5,000 sessions |Tech, Platinion, Big 4 | 9/9 personal interviews passed | 95% candidate success

Best Rote Practice

Rocket Blocks: https://www.rocketblocks.me/

Best Practice Strategy

1) Read the Economist (especially the daily graph and Financial Time frequently

https://www.economist.com/graphic-detail/2020/05/29/america-first

2) Ask case partners to focus particularly on your math skills

Quant Tips

1) Make sure you understand the numbers

2) Remind yourself of the objective / hypothesis in the case, to see where this might fit

3) Find the differences -  Where does change occur? The differences are what matter

4) Talk outloud while interpreting - first, it helps you think and process your thoughts, second, it lets the interviewer provide guidance and course correct if needed.

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

Hello!

GMAT unfortunately only gets better with practicing. Good news is that there are many ways of doing so! 

There are free exams in the internet that you can use for practice (the one of LBS MBA page, Verits prep, as well as some free trials for courses such as the one of The Economist (https://gmat.economist.com/)

Hope it helps!

Cheers,

Clara

Similar Questions
Consulting
Invited for internship but rejected for fulltime
on May 09, 2024
Global
8
2.3k
Top answer by
Hagen
Coach
#1 recommended coach | >95% success rate | 8+ years consulting, 8+ years coaching and 7+ years interviewing experience
56
8 Answers
2.3k Views
+5
Consulting
Why do I never feel ready for an MBB interview ?
on Apr 18, 2025
Global
17
400+
Top answer by
Hagen
Coach
#1 recommended coach | >95% success rate | 8+ years consulting, 8+ years coaching and 7+ years interviewing experience
23
17 Answers
400+ Views
+14
Consulting
Do consultants use AI for PowerPoint or excel or anywhere in the Process??
on Aug 24, 2024
Global
7
2.2k
Top answer by
Nilay
Coach
Former McKinsey Sr Engagement Manager | Trained McKinsey interviewer (100+ interviews, 500+ coaching sessions)
50
7 Answers
2.2k Views
+4
How likely are you to recommend us to a friend or fellow student?
0 = Not likely
10 = Very likely
Thanks for your feedback! Your opinion helps us make PrepLounge even better.