Add 12/9 and 70/21
1st number: 1 3/9, 2nd number: 3 7/21
12/9 + 70/21 is 14/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 21 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 9 × 7 = 63,
12/9 = 12 × 7/9 × 7 = 84/63 - Likewise, for the 2nd fraction, since 21 × 3 = 63,
70/21 = 70 × 3/21 × 3 = 210/63 - Add the two like fractions:
84/63 + 210/63 = 84 + 210/63 = 294/63 - 294/63 simplified gives 14/3
- So, 12/9 + 70/21 = 14/3
In mixed form: 42/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/9+70/21 12/18+70/21 12/9+70/42 36/9+70/21 12/27+70/21 12/9+70/63 60/9+70/21 12/45+70/21 84/9+70/21 12/63+70/21