Add 21/84 and 24/70
21/84 + 24/70 is 83/140.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
24/70 = 24 × 6/70 × 6 = 144/420 - Add the two like fractions:
105/420 + 144/420 = 105 + 144/420 = 249/420 - 249/420 simplified gives 83/140
- So, 21/84 + 24/70 = 83/140
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84+24/70 21/84+48/70 63/84+24/70 21/84+72/70