Add 4/5 and 21/84
4/5 + 21/84 is 21/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 5 × 84 = 420,
4/5 = 4 × 84/5 × 84 = 336/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
336/420 + 105/420 = 336 + 105/420 = 441/420 - 441/420 simplified gives 21/20
- So, 4/5 + 21/84 = 21/20
In mixed form: 11/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 8/5+21/84 4/5+42/84 4/10+21/84 12/5+21/84 4/5+63/84 4/15+21/84 20/5+21/84 4/25+21/84 28/5+21/84 4/35+21/84