Add 56/15 and 80/21
1st number: 3 11/15, 2nd number: 3 17/21
56/15 + 80/21 is 264/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
56/15 = 56 × 7/15 × 7 = 392/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105 - Add the two like fractions:
392/105 + 400/105 = 392 + 400/105 = 792/105 - 792/105 simplified gives 264/35
- So, 56/15 + 80/21 = 264/35
In mixed form: 719/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/30+80/21 56/15+80/42 56/45+80/21 56/15+80/63 56/75+80/21