Add 15/21 and 20/36
15/21 + 20/36 is 80/63.
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,
15/21 = 15 × 12/21 × 12 = 180/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
20/36 = 20 × 7/36 × 7 = 140/252 - Add the two like fractions:
180/252 + 140/252 = 180 + 140/252 = 320/252 - 320/252 simplified gives 80/63
- So, 15/21 + 20/36 = 80/63
In mixed form: 117/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/21+20/36 15/21+40/36 15/42+20/36 15/21+20/72 45/21+20/36 15/21+60/36 15/63+20/36 75/21+20/36