Add 9/42 and 21/12
1st number: 9/42, 2nd number: 1 9/12
9/42 + 21/12 is 55/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
9/42 = 9 × 2/42 × 2 = 18/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
21/12 = 21 × 7/12 × 7 = 147/84 - Add the two like fractions:
18/84 + 147/84 = 18 + 147/84 = 165/84 - 165/84 simplified gives 55/28
- So, 9/42 + 21/12 = 55/28
In mixed form: 127/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 18/42+21/12 9/42+42/12 9/84+21/12 9/42+21/24 27/42+21/12 9/42+63/12 9/42+21/36 45/42+21/12 9/42+21/60 63/42+21/12 9/42+21/84