Add 56/63 and 21/81
56/63 + 21/81 is 31/27.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 81 is 567
Next, find the equivalent fraction of both fractional numbers with denominator 567 - For the 1st fraction, since 63 × 9 = 567,
56/63 = 56 × 9/63 × 9 = 504/567 - Likewise, for the 2nd fraction, since 81 × 7 = 567,
21/81 = 21 × 7/81 × 7 = 147/567 - Add the two like fractions:
504/567 + 147/567 = 504 + 147/567 = 651/567 - 651/567 simplified gives 31/27
- So, 56/63 + 21/81 = 31/27
In mixed form: 14/27
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/63+42/81 56/63+63/81