Add 9/30 and 21/28
9/30 + 21/28 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 28 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 30 × 14 = 420,
9/30 = 9 × 14/30 × 14 = 126/420 - Likewise, for the 2nd fraction, since 28 × 15 = 420,
21/28 = 21 × 15/28 × 15 = 315/420 - Add the two like fractions:
126/420 + 315/420 = 126 + 315/420 = 441/420 - 441/420 simplified gives 21/20
- So, 9/30 + 21/28 = 21/20
In mixed form: 11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/30+21/28 9/30+42/28 9/60+21/28 9/30+21/56 27/30+21/28 9/30+63/28 9/90+21/28 9/30+21/84 45/30+21/28 63/30+21/28