Add 8/15 and 12/21
8/15 + 12/21 is 116/105.
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,
8/15 = 8 × 7/15 × 7 = 56/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
12/21 = 12 × 5/21 × 5 = 60/105 - Add the two like fractions:
56/105 + 60/105 = 56 + 60/105 = 116/105 - So, 8/15 + 12/21 = 116/105
In mixed form: 111/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/15+12/21 8/15+24/21 8/30+12/21 8/15+12/42 24/15+12/21 8/15+36/21 8/45+12/21 8/15+12/63 40/15+12/21 8/15+60/21 8/75+12/21 56/15+12/21 8/15+84/21