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Fraction to Percentage Benchmarks

Convert fractions to percentages using memorized benchmarks.

When to use

Problems like '3/8 = ?%' or needing quick fraction-to-percent conversion.

Steps

  1. 1.Check if it matches a known benchmark fraction
  2. 2.If not, find the nearest benchmark and interpolate
  3. 3.Or divide numerator by denominator and multiply by 100

Example: 3/8 = ?%

1/8 = 12.5%

3/8 = 3 x 12.5% = 37.5%

Mental approach

Memorize key fractions: 1/3 ≈ 33%, 1/4 = 25%, 1/5 = 20%, 1/6 ≈ 17%, 1/8 = 12.5%.

Pen & paper approach

Long division of numerator / denominator, multiply result by 100.

Tips

  • •Key benchmarks: 1/3=33.3%, 2/3=66.7%, 1/4=25%, 3/4=75%
  • •1/5=20%, 1/6=16.7%, 1/8=12.5%
  • •For 5ths: multiply numerator by 20. 3/5 = 3x20 = 60%
  • •For 4ths: multiply numerator by 25. 3/4 = 3x25 = 75%

Try it yourself

2/5 = ?%

5/8 = ?%

2/3 = ?%