Add 15/21 and 70/9
1st number: 15/21, 2nd number: 7 7/9
15/21 + 70/9 is 535/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
15/21 = 15 × 3/21 × 3 = 45/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
70/9 = 70 × 7/9 × 7 = 490/63 - Add the two like fractions:
45/63 + 490/63 = 45 + 490/63 = 535/63 - So, 15/21 + 70/9 = 535/63
In mixed form: 831/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+70/9 15/42+70/9 15/21+70/18 45/21+70/9 15/63+70/9 15/21+70/27 75/21+70/9 15/21+70/45 15/21+70/63