Add 40/28 and 63/21
1st number: 1 12/28, 2nd number: 3 0/21
40/28 + 63/21 is 31/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 28 × 3 = 84,
40/28 = 40 × 3/28 × 3 = 120/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
63/21 = 63 × 4/21 × 4 = 252/84 - Add the two like fractions:
120/84 + 252/84 = 120 + 252/84 = 372/84 - 372/84 simplified gives 31/7
- So, 40/28 + 63/21 = 31/7
In mixed form: 43/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/28+63/21 40/56+63/21 40/28+63/42 40/84+63/21