Add 18/21 and 3/10
18/21 + 3/10 is 81/70.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
3/10 = 3 × 21/10 × 21 = 63/210 - Add the two like fractions:
180/210 + 63/210 = 180 + 63/210 = 243/210 - 243/210 simplified gives 81/70
- So, 18/21 + 3/10 = 81/70
In mixed form: 111/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/21+3/10 18/21+6/10 18/42+3/10 18/21+3/20 54/21+3/10 18/21+9/10 18/63+3/10 18/21+3/30 90/21+3/10 18/21+15/10 18/21+3/50 18/21+21/10 18/21+3/70