Add 21/35 and 21/40
21/35 + 21/40 is 9/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 40 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 35 × 8 = 280,
21/35 = 21 × 8/35 × 8 = 168/280 - Likewise, for the 2nd fraction, since 40 × 7 = 280,
21/40 = 21 × 7/40 × 7 = 147/280 - Add the two like fractions:
168/280 + 147/280 = 168 + 147/280 = 315/280 - 315/280 simplified gives 9/8
- So, 21/35 + 21/40 = 9/8
In mixed form: 11/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/35+21/40 21/35+42/40 21/70+21/40 21/35+21/80 63/35+21/40 21/35+63/40