Add 21/20 and 42/28
1st number: 1 1/20, 2nd number: 1 14/28
21/20 + 42/28 is 51/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 28 is 140
Next, find the equivalent fraction of both fractional numbers with denominator 140 - For the 1st fraction, since 20 × 7 = 140,
21/20 = 21 × 7/20 × 7 = 147/140 - Likewise, for the 2nd fraction, since 28 × 5 = 140,
42/28 = 42 × 5/28 × 5 = 210/140 - Add the two like fractions:
147/140 + 210/140 = 147 + 210/140 = 357/140 - 357/140 simplified gives 51/20
- So, 21/20 + 42/28 = 51/20
In mixed form: 211/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/20+42/28 21/20+84/28 21/40+42/28 21/20+42/56 63/20+42/28 21/60+42/28 21/20+42/84