Add 9/15 and 21/56
9/15 + 21/56 is 39/40.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 15 × 56 = 840,
9/15 = 9 × 56/15 × 56 = 504/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
21/56 = 21 × 15/56 × 15 = 315/840 - Add the two like fractions:
504/840 + 315/840 = 504 + 315/840 = 819/840 - 819/840 simplified gives 39/40
- So, 9/15 + 21/56 = 39/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/15+21/56 9/15+42/56 9/30+21/56 27/15+21/56 9/15+63/56 9/45+21/56 45/15+21/56 9/75+21/56 63/15+21/56