Add 1/21 and 3/9
1/21 + 3/9 is 8/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 9 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
1/21 = 1 × 3/21 × 3 = 3/63 - Likewise, for the 2nd fraction, since 9 × 7 = 63,
3/9 = 3 × 7/9 × 7 = 21/63 - Add the two like fractions:
3/63 + 21/63 = 3 + 21/63 = 24/63 - 24/63 simplified gives 8/21
- So, 1/21 + 3/9 = 8/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/21+3/9 1/21+6/9 1/42+3/9 1/21+3/18 3/21+3/9 1/63+3/9 1/21+3/27 5/21+3/9 1/21+15/9 1/21+3/45 7/21+3/9 1/21+21/9 1/21+3/63