Add 21/28 and 21/56
21/28 + 21/56 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 56 is 56
Next, find the equivalent fraction of both fractional numbers with denominator 56 - For the 1st fraction, since 28 × 2 = 56,
21/28 = 21 × 2/28 × 2 = 42/56 - Likewise, for the 2nd fraction, since 56 × 1 = 56,
21/56 = 21 × 1/56 × 1 = 21/56 - Add the two like fractions:
42/56 + 21/56 = 42 + 21/56 = 63/56 - 63/56 simplified gives 9/8
- So, 21/28 + 21/56 = 9/8
In mixed form: 11/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/28+21/56 21/28+42/56 21/56+21/56 63/28+21/56 21/28+63/56 21/84+21/56