Add 21/30 and 15/9
1st number: 21/30, 2nd number: 1 6/9
21/30 + 15/9 is 71/30.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 9 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 30 × 3 = 90,
21/30 = 21 × 3/30 × 3 = 63/90 - Likewise, for the 2nd fraction, since 9 × 10 = 90,
15/9 = 15 × 10/9 × 10 = 150/90 - Add the two like fractions:
63/90 + 150/90 = 63 + 150/90 = 213/90 - 213/90 simplified gives 71/30
- So, 21/30 + 15/9 = 71/30
In mixed form: 211/30
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30+15/9 21/30+30/9 21/60+15/9 21/30+15/18 63/30+15/9 21/30+45/9 21/90+15/9 21/30+15/27 21/30+75/9 21/30+15/45 21/30+15/63