Add 20/21 and 9/7
1st number: 20/21, 2nd number: 1 2/7
20/21 + 9/7 is 47/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
20/21 = 20 × 1/21 × 1 = 20/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
9/7 = 9 × 3/7 × 3 = 27/21 - Add the two like fractions:
20/21 + 27/21 = 20 + 27/21 = 47/21 - So, 20/21 + 9/7 = 47/21
In mixed form: 25/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/21+9/7 20/21+18/7 20/42+9/7 20/21+9/14 60/21+9/7 20/21+27/7 20/63+9/7 20/21+9/21 20/21+45/7 20/21+9/35 20/21+63/7 20/21+9/49