Add 12/15 and 12/21
12/15 + 12/21 is 48/35.
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,
12/15 = 12 × 7/15 × 7 = 84/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
12/21 = 12 × 5/21 × 5 = 60/105 - Add the two like fractions:
84/105 + 60/105 = 84 + 60/105 = 144/105 - 144/105 simplified gives 48/35
- So, 12/15 + 12/21 = 48/35
In mixed form: 113/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/15+12/21 12/15+24/21 12/30+12/21 12/15+12/42 36/15+12/21 12/15+36/21 12/45+12/21 12/15+12/63 60/15+12/21 12/15+60/21 12/75+12/21 84/15+12/21 12/15+84/21