Smart Math guide · Fractions, Decimals & Percent

Work Backward from a Percent

When a final amount represents a known percent of the original, divide by the decimal multiplier.

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The method

How to use it

  1. Translate the statement into final = multiplier × original.
  2. Identify the multiplier.
  3. Divide final by the multiplier.
Worked example

See it in action

After a 20% discount, $64 is 80% of original: 64÷0.8=$80.

Check your thinking

How to verify it

20% of $80 is $16; $80−$16=$64.

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