Add 30/21 and 12/28
1st number: 1 9/21, 2nd number: 12/28
30/21 + 12/28 is 13/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 28 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
30/21 = 30 × 4/21 × 4 = 120/84 - Likewise, for the 2nd fraction, since 28 × 3 = 84,
12/28 = 12 × 3/28 × 3 = 36/84 - Add the two like fractions:
120/84 + 36/84 = 120 + 36/84 = 156/84 - 156/84 simplified gives 13/7
- So, 30/21 + 12/28 = 13/7
In mixed form: 16/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/21+12/28 30/21+24/28 30/42+12/28 30/21+12/56 90/21+12/28 30/21+36/28 30/63+12/28 30/21+12/84 30/21+60/28 30/21+84/28