Add 18/3 and 42/21
1st number: 6 0/3, 2nd number: 2 0/21
18/3 + 42/21 is 8/1.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 21 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 3 × 7 = 21,
18/3 = 18 × 7/3 × 7 = 126/21 - Likewise, for the 2nd fraction, since 21 × 1 = 21,
42/21 = 42 × 1/21 × 1 = 42/21 - Add the two like fractions:
126/21 + 42/21 = 126 + 42/21 = 168/21 - 168/21 simplified gives 8/1
- So, 18/3 + 42/21 = 8/1
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/3+42/21 18/3+84/21 18/6+42/21 54/3+42/21 18/9+42/21 18/3+42/63 90/3+42/21 18/15+42/21 18/21+42/21