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