Add 15/21 and 21/24
15/21 + 21/24 is 89/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 24 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 21 × 8 = 168,
15/21 = 15 × 8/21 × 8 = 120/168 - Likewise, for the 2nd fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168 - Add the two like fractions:
120/168 + 147/168 = 120 + 147/168 = 267/168 - 267/168 simplified gives 89/56
- So, 15/21 + 21/24 = 89/56
In mixed form: 133/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+21/24 15/21+42/24 15/42+21/24 15/21+21/48 45/21+21/24 15/21+63/24 15/63+21/24 15/21+21/72 75/21+21/24