Add 21/15 and 12/56
1st number: 1 6/15, 2nd number: 12/56
21/15 + 12/56 is 113/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 56 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 15 × 56 = 840,
21/15 = 21 × 56/15 × 56 = 1176/840 - Likewise, for the 2nd fraction, since 56 × 15 = 840,
12/56 = 12 × 15/56 × 15 = 180/840 - Add the two like fractions:
1176/840 + 180/840 = 1176 + 180/840 = 1356/840 - 1356/840 simplified gives 113/70
- So, 21/15 + 12/56 = 113/70
In mixed form: 143/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/15+12/56 21/15+24/56 21/30+12/56 63/15+12/56 21/15+36/56 21/45+12/56 21/15+60/56 21/75+12/56 21/15+84/56