Add 12/30 and 15/21
12/30 + 15/21 is 39/35.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
12/30 = 12 × 7/30 × 7 = 84/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
15/21 = 15 × 10/21 × 10 = 150/210 - Add the two like fractions:
84/210 + 150/210 = 84 + 150/210 = 234/210 - 234/210 simplified gives 39/35
- So, 12/30 + 15/21 = 39/35
In mixed form: 14/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/30+15/21 12/30+30/21 12/60+15/21 12/30+15/42 36/30+15/21 12/30+45/21 12/90+15/21 12/30+15/63 60/30+15/21 12/30+75/21 84/30+15/21