Fractions, decimals and percentages

Fractions, decimals and percentages are three ways of writing the same amount. Percent means “out of 100”. Learn the common ones by heart and the rest follow.

Key facts

  • 1/2 = 0.5 = 50%, 1/4 = 0.25 = 25%, 3/4 = 0.75 = 75%
  • 1/5 = 0.2 = 20%, 1/10 = 0.1 = 10%, 1/3 ≈ 0.333 = 33 1/3%
  • Fraction → decimal: divide the top by the bottom.
  • Decimal → percentage: × 100.

Worked examples

Example 1

Write 3/8 as a decimal and a percentage.

  1. Divide the top by the bottom. 3 ÷ 8 = 0.375
  2. × 100 for a percentage. 37.5%

Answer: 0.375 = 37.5%

Example 2

Put in order, smallest first: 0.62, 3/5, 65%.

  1. Convert. 3/5 = 0.6, 65% = 0.65
  2. Compare 0.6, 0.62, 0.65. 3/5, 0.62, 65%

Answer: 3/5, 0.62, 65%