Add 18/12 and 21/15
1st number: 1 6/12, 2nd number: 1 6/15
18/12 + 21/15 is 29/10.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 15 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
18/12 = 18 × 5/12 × 5 = 90/60 - Likewise, for the 2nd fraction, since 15 × 4 = 60,
21/15 = 21 × 4/15 × 4 = 84/60 - Add the two like fractions:
90/60 + 84/60 = 90 + 84/60 = 174/60 - 174/60 simplified gives 29/10
- So, 18/12 + 21/15 = 29/10
In mixed form: 29/10
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/12+21/15 18/12+42/15 18/24+21/15 18/12+21/30 54/12+21/15 18/12+63/15 18/36+21/15 18/12+21/45 90/12+21/15 18/60+21/15 18/12+21/75 18/84+21/15