4.2 as a Fraction

4.2 as a fraction is 21/5. As a mixed number that is 4 1/5.

How to convert 4.2 to a fraction

  1. 4.2 has one decimal place, so write it over 10 (a 1 followed by 1 zero) with the decimal point removed: 4.2 = 42/10.
  2. Find the greatest common divisor of 42 and 10: it is 2.
  3. Divide both by 2: 42 ÷ 2 = 21 and 10 ÷ 2 = 5.
  4. The answer is 21/5.

Since 21 is larger than 5, you can also write it as the mixed number 4 1/5: 21 ÷ 5 = 4 remainder 1.

Check

Divide the numerator by the denominator: 21 ÷ 5 = 4.2. As a percent, 4.2 = 420%.

Similar decimals

DecimalFraction
4.06203/50
4.08102/25
4.141/10
4.12533/8
4.1583/20
4.2517/4
4.343/10
4.3587/20

See also: 21/5 as a mixed number.

Another decimal? Use the decimal to fraction converter or browse the decimal to fraction chart.