Add 21/30 and 12/35
21/30 + 12/35 is 73/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 35 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
21/30 = 21 × 7/30 × 7 = 147/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
12/35 = 12 × 6/35 × 6 = 72/210 - Add the two like fractions:
147/210 + 72/210 = 147 + 72/210 = 219/210 - 219/210 simplified gives 73/70
- So, 21/30 + 12/35 = 73/70
In mixed form: 13/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/30+12/35 21/30+24/35 21/60+12/35 21/30+12/70 63/30+12/35 21/30+36/35 21/90+12/35 21/30+60/35 21/30+84/35