Answers

Subtract 81/3 from 20/42

1^st number: 20/42, 2^nd number: 27 0/3

20/42 - 81/3 is -557/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 3 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 42 × 1 = 42,
   20/42 = 20 × 1/42 × 1 = 20/42
3. Likewise, for the 2nd fraction, since 3 × 14 = 42,
   81/3 = 81 × 14/3 × 14 = 1134/42
4. Subtract the two like fractions:
   20/42 - 1134/42 = 20 - 1134/42 = -1114/42
5. After reducing the fraction, the answer is -557/21

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad

Related: ⁴⁰/₄₂-⁸¹/₃ ²⁰/₈₄-⁸¹/₃ ²⁰/₄₂-⁸¹/₆ ⁶⁰/₄₂-⁸¹/₃ ²⁰/₄₂-⁸¹/₉ ²⁰/₄₂-⁸¹/₁₅ ²⁰/₄₂-⁸¹/₂₁

Subtract Fractions Calculator