Add 15/21 and 10/18
15/21 + 10/18 is 80/63.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
15/21 = 15 × 6/21 × 6 = 90/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
10/18 = 10 × 7/18 × 7 = 70/126 - Add the two like fractions:
90/126 + 70/126 = 90 + 70/126 = 160/126 - 160/126 simplified gives 80/63
- So, 15/21 + 10/18 = 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+10/18 15/21+20/18 15/42+10/18 15/21+10/36 45/21+10/18 15/21+30/18 15/63+10/18 15/21+10/54 75/21+10/18 15/21+50/18 15/21+10/90 15/21+70/18