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Eyeballing percentage calculations

Is there a way to improve eyeballing percentage calculations (eg. (5/25 = 20%) without writing down the math? Do you just memorize what %  fractions constitute? (Eg 1/5 = 20%, 1/4 = 25%)

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Top answer
Deleted user
edited on Jul 24, 2021

I would suggest to start practicing mental math on dialy basis (many websites/apps can help), then you will come up with your own shortcuts.

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Ian
Coach
on Jul 22, 2021
Top US BCG / MBB Coach - 5,000 sessions |Tech, Platinion, Big 4 | 9/9 personal interviews passed | 95% candidate success

Hi there,

Yes, you need to "memorize" and practice! Find online tests (preplounge, mathdrills, etc). and just run through the percents.

The better you can get at fast math, the more of your brainpower/focus that can be spent on the rest of the case/interview!

Florian
Coach
on Jul 23, 2021
1400 5-star reviews across platforms | 600+ offers | Highest-rated case book on Amazon | Uni lecturer in US, Asia, EU

Hey there,

Definitely! 

  • Google ''fraction table case interview'', print it out, and memorize it
  • Use the PrepLounge Math tool to conduct math drills for 1-2 hours a day, depending on how much of a weakness it is for you.

It is always refreshing to see when a candidate is brushing through the math section with ease and accuracy, which is solely a learned skill --> There are no excuses to not perform at your best in this section.

Cheers,

Florian

Agrim
Coach
on Jul 24, 2021
Top Awarded Coach | BCG Dubai Project Leader | Master Casing in only 3 Hours | 10y in Consulting | Free Intro Call

Hi Anon,

Your best tool here is practice. Nothing else.

The more you look at such ratios, the more intuitive they will become.

If you try to memorize them you will fumble at some point, and you will also be spending valuable mental resources in memorizing something that doesn't need to be memorized.

Take lots of drills and practice a lot. It will come.

Hope this helps!

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