Add 42/20 and 21/18
1st number: 2 2/20, 2nd number: 1 3/18
42/20 + 21/18 is 49/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 18 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 20 × 9 = 180,
42/20 = 42 × 9/20 × 9 = 378/180 - Likewise, for the 2nd fraction, since 18 × 10 = 180,
21/18 = 21 × 10/18 × 10 = 210/180 - Add the two like fractions:
378/180 + 210/180 = 378 + 210/180 = 588/180 - 588/180 simplified gives 49/15
- So, 42/20 + 21/18 = 49/15
In mixed form: 34/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/20+21/18 42/20+42/18 42/40+21/18 42/20+21/36 42/20+63/18 42/60+21/18 42/20+21/54 42/20+21/90