Add 21/28 and 3/20
21/28 + 3/20 is 9/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 20 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 28 × 5 = 140,
21/28 = 21 × 5/28 × 5 = 105/140 - Likewise, for the 2nd fraction, since 20 × 7 = 140,
3/20 = 3 × 7/20 × 7 = 21/140 - Add the two like fractions:
105/140 + 21/140 = 105 + 21/140 = 126/140 - 126/140 simplified gives 9/10
- So, 21/28 + 3/20 = 9/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/28+3/20 21/28+6/20 21/56+3/20 21/28+3/40 63/28+3/20 21/28+9/20 21/84+3/20 21/28+3/60 21/28+15/20 21/28+21/20