Add 81/15 and 21/18
1st number: 5 6/15, 2nd number: 1 3/18
81/15 + 21/18 is 197/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 15 × 6 = 90,
81/15 = 81 × 6/15 × 6 = 486/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
21/18 = 21 × 5/18 × 5 = 105/90 - Add the two like fractions:
486/90 + 105/90 = 486 + 105/90 = 591/90 - 591/90 simplified gives 197/30
- So, 81/15 + 21/18 = 197/30
In mixed form: 617/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/15+42/18 81/30+21/18 81/15+21/36 81/15+63/18 81/45+21/18 81/15+21/54 81/75+21/18 81/15+21/90