Add 3/12 and 21/7
1st number: 3/12, 2nd number: 3 0/7
3/12 + 21/7 is 13/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
3/12 = 3 × 7/12 × 7 = 21/84 - Likewise, for the 2nd fraction, since 7 × 12 = 84,
21/7 = 21 × 12/7 × 12 = 252/84 - Add the two like fractions:
21/84 + 252/84 = 21 + 252/84 = 273/84 - 273/84 simplified gives 13/4
- So, 3/12 + 21/7 = 13/4
In mixed form: 31/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/12+21/7 3/12+42/7 3/24+21/7 3/12+21/14 9/12+21/7 3/12+63/7 3/36+21/7 15/12+21/7 3/60+21/7 3/12+21/35 21/12+21/7 3/84+21/7 3/12+21/49