Add 3/7 and 21/70
3/7 + 21/70 is 51/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 7 and 70 is 70
Next, find the equivalent fraction of both fractional numbers with denominator 70 - For the 1st fraction, since 7 × 10 = 70,
3/7 = 3 × 10/7 × 10 = 30/70 - Likewise, for the 2nd fraction, since 70 × 1 = 70,
21/70 = 21 × 1/70 × 1 = 21/70 - Add the two like fractions:
30/70 + 21/70 = 30 + 21/70 = 51/70 - So, 3/7 + 21/70 = 51/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/7+21/70 3/7+42/70 3/14+21/70 9/7+21/70 3/7+63/70 3/21+21/70 15/7+21/70 3/35+21/70 21/7+21/70 3/49+21/70