Add 10/40 and 21/70
10/40 + 21/70 is 11/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 70 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 40 × 7 = 280,
10/40 = 10 × 7/40 × 7 = 70/280 - Likewise, for the 2nd fraction, since 70 × 4 = 280,
21/70 = 21 × 4/70 × 4 = 84/280 - Add the two like fractions:
70/280 + 84/280 = 70 + 84/280 = 154/280 - 154/280 simplified gives 11/20
- So, 10/40 + 21/70 = 11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/40+21/70 10/40+42/70 10/80+21/70 30/40+21/70 10/40+63/70 50/40+21/70 70/40+21/70