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Math's relevance final round

How important are the maths at the case interview really? Let's suppose that when you reach the maths part you (i) explain the steps you are going to take (ii) ask for the data that is missing and you need and (iii) once you reach the arithmetic part you mess some numbers due to pressure (i.e 2+2 = 5)

Is such a big deal? I think it's more about how you structure the problem and whether you identify the data needed than actually performing perfect calculations....

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Top answer
Deleted user
on Jun 05, 2021

Only of you get the structure right and work through the case systematically and end up with a minor calculation error and a honest mistake then its no biggie. Otherwise this can hurt the outcome for you. Important thing is for you to spot the mistake and correct it before the interviewer does. But 2+2 =5 is not acceptable :). There is a reason for calculations in a case- to test your attention to detail and whether you are safe pair of hands. So, every part is important overall in the grand scheme of things. Its not about doing calculations in your head or doing them very quickly.

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Ian
Coach
on Jun 05, 2021
Top US BCG / MBB Coach - 5,000 sessions |Tech, Platinion, Big 4 | 9/9 personal interviews passed | 95% candidate success

Hi there,

Maths are essentially table stakes in a case. So, you need to be able to do it, in order to get outcomes/conclusions.

Ultimately, if you have a structured approach (to both the case and the math), you articulate it clearly + concisely, and you drive forward, gain insights, and solve the problem, then a small math mistake isn't a big deal (importantly, you do still need to catch it/allow yourself to be corrected, and fix the mistake)

Ken
Coach
on Jun 06, 2021
Ex-McKinsey final round interviewer | Executive Coach

I would say they are equally important. It's easier to impress your interviewer with your ability to structure and identify variables, at the same time, if the maths is weak it's concerning. Having said that, I struggle to imagine such candidate. 

Quatitative thinking including comfort with arithmetics is important in the role. If your mistake is clearly just a silly mistake then most final round interviewers will see past it. If there's consistent issue then many will struggle to see you being able to do the job well.

on Jun 06, 2021

Both are important. Math might be "easier" to prepare for than strong structuring skills but it is one of the fundamental aspects interviewers and companies look out for.

10
Florian
Coach
on Jun 07, 2021
1400 5-star reviews across platforms | 600+ offers | Highest-rated case book on Amazon | Uni lecturer in US, Asia, EU

Hey there,

In short, its about both

(i) structuring the approach

(ii) performing the calculations accurately and swiftly

In practice, the big picture counts, and your mistake will be evaluated in the context of all other case interviews and the performance in that specific interview, respectively.

To make it a bit clearer: If you bombed more than one calculation and had a good but not excellent performance throughout all cases, this could turn out unfavorably. If this was your only blunder and the rest of the interviews went very well, it will likely not matter all that much.

Cheers,

Florian

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