Add 5/21 and 5/7
5/21 + 5/7 is 20/21.
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,
5/21 = 5 × 1/21 × 1 = 5/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
5/7 = 5 × 3/7 × 3 = 15/21 - Add the two like fractions:
5/21 + 15/21 = 5 + 15/21 = 20/21 - So, 5/21 + 5/7 = 20/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/21+5/7 5/21+10/7 5/42+5/7 5/21+5/14 15/21+5/7 5/21+15/7 5/63+5/7 5/21+5/21 25/21+5/7 5/21+25/7 5/21+5/35 35/21+5/7 5/21+35/7 5/21+5/49