Add 21/80 and 35/70
21/80 + 35/70 is 61/80.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 70 is 560
Next, find the equivalent fraction of both fractional numbers with denominator 560 - For the 1st fraction, since 80 × 7 = 560,
21/80 = 21 × 7/80 × 7 = 147/560 - Likewise, for the 2nd fraction, since 70 × 8 = 560,
35/70 = 35 × 8/70 × 8 = 280/560 - Add the two like fractions:
147/560 + 280/560 = 147 + 280/560 = 427/560 - 427/560 simplified gives 61/80
- So, 21/80 + 35/70 = 61/80
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/80+35/70 63/80+35/70