Will it look bad to count my fingers while doing math during the interview?

I am currently practicing mental math to prepare for consulting case interviews. (looking to apply for the big 4 accounting firm consulting department or Accenture, because MBB don’t really recruit from my school)

Will it look bad to count my fingers while doing math during the interview? In addition, is it bad to do long multiplication on paper during the interview?

7 Comments
 

If you want practice mental maths try - Tradermaths .com - the questions are highly customize-able, so should also be appropriate for consulting.

 
Most Helpful

Counting your fingers - I dunno, there's no rule against it, but looks kind of childish. If you want to look like a real whiz, do it well structured on paper.

E.g. 23% of 1600

Just talk through and write at the same time. "25% of 1600 is 400, less 2% of 1600 which is 32, means that 23% of 1600 is 368". Or 20% plus 3%, (320+48) most people find it easier to always add.

Write it down line by line as you go - write down 400, then write minus 32 below it, then the answer. It makes it really hard to screw up, and gives you some breathing room cuz you can write a little slow. And honestly it makes you look sharper than someone doing it all in your head. A better approach on paper with the write answer is better than an opaque approach with the crack answer every time.

Personally I think it's worth practicing the skill as well.

 

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