Add 20/7 and 42/81
1st number: 2 6/7, 2nd number: 42/81
20/7 + 42/81 is 638/189.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 7 × 81 = 567,
20/7 = 20 × 81/7 × 81 = 1620/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
42/81 = 42 × 7/81 × 7 = 294/567 - Add the two like fractions:
1620/567 + 294/567 = 1620 + 294/567 = 1914/567 - 1914/567 simplified gives 638/189
- So, 20/7 + 42/81 = 638/189
In mixed form: 371/189
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/7+42/81 20/7+84/81 20/14+42/81 60/7+42/81 20/21+42/81 20/35+42/81 20/49+42/81