Add 5/21 and 21/49
5/21 + 21/49 is 2/3.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
5/21 = 5 × 7/21 × 7 = 35/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
21/49 = 21 × 3/49 × 3 = 63/147 - Add the two like fractions:
35/147 + 63/147 = 35 + 63/147 = 98/147 - 98/147 simplified gives 2/3
- So, 5/21 + 21/49 = 2/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/21+21/49 5/21+42/49 5/42+21/49 5/21+21/98 15/21+21/49 5/21+63/49 5/63+21/49 25/21+21/49 35/21+21/49