Add 18/20 and 21/84
18/20 + 21/84 is 23/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 84 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
18/20 = 18 × 21/20 × 21 = 378/420 - Likewise, for the 2nd fraction, since 84 × 5 = 420,
21/84 = 21 × 5/84 × 5 = 105/420 - Add the two like fractions:
378/420 + 105/420 = 378 + 105/420 = 483/420 - 483/420 simplified gives 23/20
- So, 18/20 + 21/84 = 23/20
In mixed form: 13/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/20+21/84 18/20+42/84 18/40+21/84 54/20+21/84 18/20+63/84 18/60+21/84 90/20+21/84