Add 1/21 and 15/36
1/21 + 15/36 is 13/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
1/21 = 1 × 12/21 × 12 = 12/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
15/36 = 15 × 7/36 × 7 = 105/252 - Add the two like fractions:
12/252 + 105/252 = 12 + 105/252 = 117/252 - 117/252 simplified gives 13/28
- So, 1/21 + 15/36 = 13/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/21+15/36 1/21+30/36 1/42+15/36 1/21+15/72 3/21+15/36 1/21+45/36 1/63+15/36 5/21+15/36 1/21+75/36 7/21+15/36