Add 20/21 and 3/20
20/21 + 3/20 is 463/420.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 21 × 20 = 420,
20/21 = 20 × 20/21 × 20 = 400/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
3/20 = 3 × 21/20 × 21 = 63/420 - Add the two like fractions:
400/420 + 63/420 = 400 + 63/420 = 463/420 - So, 20/21 + 3/20 = 463/420
In mixed form: 143/420
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+3/20 20/21+6/20 20/42+3/20 20/21+3/40 60/21+3/20 20/21+9/20 20/63+3/20 20/21+3/60 20/21+15/20 20/21+21/20