Add 12/42 and 21/49
12/42 + 21/49 is 5/7.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 49 is 294
Next, find the equivalent fraction of both fractional numbers with denominator 294 - For the 1st fraction, since 42 × 7 = 294,
12/42 = 12 × 7/42 × 7 = 84/294 - Likewise, for the 2nd fraction, since 49 × 6 = 294,
21/49 = 21 × 6/49 × 6 = 126/294 - Add the two like fractions:
84/294 + 126/294 = 84 + 126/294 = 210/294 - 210/294 simplified gives 5/7
- So, 12/42 + 21/49 = 5/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/42+21/49 12/42+42/49 12/84+21/49 12/42+21/98 36/42+21/49 12/42+63/49 60/42+21/49 84/42+21/49