What are some common finance/math formulas that one might expect at a BCG interview? Will these be given if you don’t know them?

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What are some common finance/math formulas that one might expect at a BCG interview? Will these be given if you don’t know them?

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4 answers

Hi,

Here is a set of things you need to know:

**1) Math and formulas:**

- Interest rates calculations
- Compound margin
- NPV using the Rule of 72, Perpetuity
- CAGR using the Rule of 72
- Currencies exchange calculations
- Speed, time, distance calculations
- Equations, systems of equations
- Ratio & Proportions
- Little's Law
- Solving the problems by calculating the area of the triangle
- Profit / breakeven formula
- Correlations, outliers (being able to spot on the graphs, tables)

**2) Fast math skills**

- Rounding up and down
- Learn how to multiply double digit numbers (https://www.youtube.com/watch?v=6ndkkPZYJHo)
- Learn the division table up to 1/11 (i.e. 5/6 = 83.3)
- Learn how to work with zeros using powers (e.g.: 4000000 = 4*10ˆ6)

Use math tools (Mimir math for iOS), Math tool on Viktor Cheng website to practice

**3) Working with tables and graphs and deriving conclusions**

- Study "Say it with Charts" book
- Check all available MBB presentations and publications. Practice to derive conclusions and check yourself with the actual ones from the article / presentation
- GMAT IR part (Official guide and Manhattan prep)
- Learn basic statistics (Any GMAT or MBA prep guides)

Good luck!

Hi Anonymous,

these are the most common formulas I encountered/have been useful through my interview process at BCG:

- Breakeven point
- Rule of 72 (for quickly computation of compound rates)
- Perpetuity formula (for quick valuation estimates) and general NPV formula

I would not expect any interviewer to provide any of them in case you don’t know (or if they provide I don’t think they would move you to the next round).

Besides that, you should also be familiar with simple and compound interest, and could be useful to be updated on the main currency exchanges, oil and gold prices.

Finally would recommend reviewing the formulas for volume/surface of main solid figures (pyramid, cone, cylinder, sphere), which could be useful in market sizing cases.

Best,

Francesco

Very interesting, for North America perspective I find requirements for financial knowledge to be wildly different from the ones outlined in other answers.

Unless you are an MBA, a finance major or worked in finance I do not expect any knowledge of the formulas - with the exception of NPV - and I will indeed explain the relevant formulas to you if needed. Also would never expect you to calculate the NPV of a series of cash-flows during an interview due to the computational heaviness of that.

Finally, the rule of 72 is a nice tool but if candidate uses it during the interview then I would ask the mathematical explanation behind it. If you don’t that would be detrimental. This because To be an excellent consultant is very important that you know and understand the tools that you use intimately and understand how they work, their limitations, etc.

What I do expect is that you ace the basics like multiplications and divisions. I know, it sounds, well, basic, but if you have an hesitation on telling me what is 2% of 5M or calculate 0.6/9 that would be almost a non starter.

Finally when we do math I would like to see if you can get to the results in the simplest and fastest way possible. This will show me whether in a case you are trying to complicate things uneccessarely.

hope it helps,

Andrea

Hi Anonym,

I worked at BCG until recently

If you like, just write me and we can have a call

Best regards

Marco-Alexander

Case Interviews can be led by the candidate or by the interviewer: In Candidate-led cases the main challenge is the structure. In Interviewer-led cases the main challenge is to adapt quickly