Ben Stephen's viral tweet reveals a surprisingly simple solution on how to calculate percentages. Why weren't we taught this in school?
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Percentage Trick - Solve precentages mentally - percentages made easy with the cool math trick!
Solve Percentages in Your Head in seconds -» Easy Percentage Trick
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How to calculate percentages in your head
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Ingenious Math Trick Reveals How to Calculte Percentages in Your Head
I spent 2 minutes doing mental math every day for 50 days in a row
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Amazing trick
