Answers

Add 18/42 and 84/81

1^st number: 18/42, 2^nd number: 1 3/81

18/42 + 84/81 is 277/189.

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,
   18/42 = 18 × 27/42 × 27 = 486/1134
3. Likewise, for the 2nd fraction, since 81 × 14 = 1134,
   84/81 = 84 × 14/81 × 14 = 1176/1134
4. Add the two like fractions:
   486/1134 + 1176/1134 = 486 + 1176/1134 = 1662/1134
5. 1662/1134 simplified gives 277/189
6. So, 18/42 + 84/81 = 277/189
   In mixed form: 188/189

MathStep (Works offline)

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

Related: ³⁶/₄₂+⁸⁴/₈₁ ¹⁸/₈₄+⁸⁴/₈₁ ⁵⁴/₄₂+⁸⁴/₈₁ ⁹⁰/₄₂+⁸⁴/₈₁

Add Fractions Calculator