Add 21/28 and 54/56
21/28 + 54/56 is 12/7.
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,
54/56 = 54 × 1/56 × 1 = 54/56 - Add the two like fractions:
42/56 + 54/56 = 42 + 54/56 = 96/56 - 96/56 simplified gives 12/7
- So, 21/28 + 54/56 = 12/7
In mixed form: 15/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/28+54/56 21/56+54/56 63/28+54/56 21/84+54/56