Add 12/30 and 28/21
1st number: 12/30, 2nd number: 1 7/21
12/30 + 28/21 is 26/15.
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,
28/21 = 28 × 10/21 × 10 = 280/210 - Add the two like fractions:
84/210 + 280/210 = 84 + 280/210 = 364/210 - 364/210 simplified gives 26/15
- So, 12/30 + 28/21 = 26/15
In mixed form: 111/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/30+28/21 12/30+56/21 12/60+28/21 12/30+28/42 36/30+28/21 12/30+84/21 12/90+28/21 12/30+28/63 60/30+28/21 84/30+28/21