Can I use the phrase "Using the rule of 72 we see that.." in a case interview? Or is it just a math trick that isn't really supposed to be so evidently exposed during calculations?
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Quick question: Using the rule of 72!
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Top answer
Vlad
on Mar 18, 2019
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McKinsey / Accenture Alum / Got all BIG3 offers / Harvard Business School
Hi,
Not sure if I understand your question. You should always provide clarity on the way you are doing the calculations. I strongly recommend telling the interviewer HOW you are going to calculate something before actually starting the calculations. So yes, you should tell this to the interviewer.
Best!
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Francesco
on Mar 18, 2019
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#1 Coach for Sessions (4.500+) | 1.500+ 5-Star Reviews | Proven Success: ➡ interviewoffers.com | Ex BCG | 10Y+ Coaching
Hi Anonymous,
as mentioned by Vlad, you can definitely mention you are using the rule of 72 - if you don’t, the interviewer will very likely ask you how you managed to calculate so quickly a compound growth. The interviewer may also ask you where the rule comes from, so be sure to review its origin, which is related to the natural logarithm.
Best,
Francesco
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