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What formulas to use during the BCG Online Case?

BCG formula Math problem
New answer on Apr 30, 2024
4 Answers
3.1 k Views
Anonymous A asked on Mar 06, 2020

When posed with a BCG Online Case question, I often can't think of what formula to use to solve it. What should I study?

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Content Creator
replied on Apr 30, 2024
#1 rated MBB & McKinsey Coach
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Content Creator
updated an answer on Aug 29, 2021
#1 Coach for Sessions (4.500+) | 1.500+ 5-Star Reviews | Proven Success (➡ | Ex BCG | 10Y+ Coaching

Hi Anonymous,

the most common formulas you need to know as part of the interview process are:

  • Breakeven point
  • Rule of 72 (usually related to calculation of CAGR)
  • Perpetuity formula and general NPV formula

Besides that, you should be familiar with simple and compound interests.

If you find challenging to structure something different from that, I would recommend to post the questions for which you find difficult to understand the formula for further support.

Additionally, if you want to prepare in the best possible way for the BCG Online Case, I created a guide exactly for that:




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Content Creator
replied on Mar 07, 2020
McKinsey | Awarded professor at Master in Management @ IE | MBA at MIT |+180 students coached | Integrated FIT Guide aut


Most people worry a lot about this, when actually there is no advanced math required in case interviews, but calculating quickly is a real challenge-

Nearly all the math required in case interviews is arithmetic: addition, subtraction, multiplication and division. You will likely need to perform these calculations with percentages, decimals or fractions, and calculate a percentage value (which requires division). Most candidates understand these math concepts; the challenge for many people is performing multiple calculations with large numbers quickly and without calculators or spreadsheets, in a high-pressure environment with a six-figure salary and your future career on the line.

Hence, it´s more about the agility and ability to keep the orders of magnitude than complicated formulas.



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Content Creator
replied on Mar 06, 2020
McKinsey | NASA | top 10 FT MBA professor for consulting interviews | 6+ years of coaching
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Cristian gave the best answer


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