Add 21/56 and 72/21
1st number: 21/56, 2nd number: 3 9/21
21/56 + 72/21 is 213/56.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
21/56 = 21 × 3/56 × 3 = 63/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
72/21 = 72 × 8/21 × 8 = 576/168 - Add the two like fractions:
63/168 + 576/168 = 63 + 576/168 = 639/168 - 639/168 simplified gives 213/56
- So, 21/56 + 72/21 = 213/56
In mixed form: 345/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/56+72/21 21/56+72/42 63/56+72/21 21/56+72/63