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Percentage Math Practice

Mark asked on Jul 18, 2018 - 1 answer

Hey guys!

I am looking for a math tool to practice calculation of percentages such as margins. The traditional mental math training tools from and preplounge only train to caclulate absolute numbers form percentage rate, but not percentages such as margins from absolute numbers. I am looking for calculations such as 25m/40m etc.

Does anyone know a tool or qa way to practice these calculations?

Best wishes!

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replied on Jul 18, 2018
McKinsey Engagement Manager & BCG Consultant | Interviewer at McK & BCG for 7 years | Coached 100+ candidates secure MBB offers
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Hi Mark,

I am not sure I understand your challenge. Performing this kind of calculations will already give you the percentage, just expressed as a decimal figure (0,625 or 62,5% in your above example).

What you can do is to just create a simple excel sheet where you generate two random numbers as numerator and denominator:


Paste this formula into two cells, and then just divide the numerator by the denominator to get the result (you can put this on a different tab to hide it if you want). Then do the calculation manually and check the correctness of your result. To generate new random numbers just place the cursor on an empty cell and hit DEL.

Cheers, Sidi

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