Math Practice

In a case interview, 95% of the time a single mental math error results in an automatic rejection. This is because firms like McKinsey, Bain and BCG cannot take the risk that you will make a mental math error in front of a client that’s paying them $1 million a month for your and your colleagues’ time.

If you are even considering a career in consulting, I can guarantee you that you already know enough math concepts to pass the case interview. It’s called addition, subtraction, multiplication and division. In consulting, we also often use percentages. That’s 90% of the math we use in the case interview. Clearly, you already know how to do that.

What you may not know how to do, or have enough real world experience doing, is doing such computations in your head, using large numbers.

For example, what is the approximate answer to 500 million divided by 150 multiplied by 15%?


One second… two seconds… three seconds…

Do you know the answer?

If you haven’t figured out the correct answer by the time you read this sentence, your current mental math skills may be too slow or not accurate enough to pass a case interview and the best advice I can give you is to start practicing now.

It is important to develop your basic math skills to a high level of proficiency while under the pressure and stress of an interview. The best way to do that is to practice your math skills while timing yourself.

Access my free math practice tool to increase your speed and accuracy while being timed in case interview math.

To get access to the FREE Math Tool and other free resources just fill the form below

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