Add 15/18 and 2/21
15/18 + 2/21 is 13/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
2/21 = 2 × 6/21 × 6 = 12/126 - Add the two like fractions:
105/126 + 12/126 = 105 + 12/126 = 117/126 - 117/126 simplified gives 13/14
- So, 15/18 + 2/21 = 13/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/18+2/21 15/18+4/21 15/36+2/21 15/18+2/42 45/18+2/21 15/18+6/21 15/54+2/21 15/18+2/63 75/18+2/21 15/18+10/21 15/90+2/21 15/18+14/21