Answers

Add 30/42 and 20/81

30/42 + 20/81 is 545/567.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 81 is 1134
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1134
2. For the 1st fraction, since 42 × 27 = 1134,
   30/42 = 30 × 27/42 × 27 = 810/1134
3. Likewise, for the 2nd fraction, since 81 × 14 = 1134,
   20/81 = 20 × 14/81 × 14 = 280/1134
4. Add the two like fractions:
   810/1134 + 280/1134 = 810 + 280/1134 = 1090/1134
5. 1090/1134 simplified gives 545/567
6. So, 30/42 + 20/81 = 545/567

MathStep (Works offline)

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

Related: ⁶⁰/₄₂+²⁰/₈₁ ³⁰/₄₂+⁴⁰/₈₁ ³⁰/₈₄+²⁰/₈₁ ⁹⁰/₄₂+²⁰/₈₁ ³⁰/₄₂+⁶⁰/₈₁

Add Fractions Calculator