Answers

Subtract 56/81 from 12/21

12/21 - 56/81 is -68/567.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   12/21 = 12 × 27/21 × 27 = 324/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   56/81 = 56 × 7/81 × 7 = 392/567
4. Subtract the two like fractions:
   324/567 - 392/567 = 324 - 392/567 = -68/567

MathStep (Works offline)

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

Related: ²⁴/₂₁-⁵⁶/₈₁ ¹²/₄₂-⁵⁶/₈₁ ³⁶/₂₁-⁵⁶/₈₁ ¹²/₆₃-⁵⁶/₈₁ ⁶⁰/₂₁-⁵⁶/₈₁ ⁸⁴/₂₁-⁵⁶/₈₁

Subtract Fractions Calculator