Add 63/12 and 42/21
1st number: 5 3/12, 2nd number: 2 0/21
63/12 + 42/21 is 29/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
63/12 = 63 × 7/12 × 7 = 441/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Add the two like fractions:
441/84 + 168/84 = 441 + 168/84 = 609/84 - 609/84 simplified gives 29/4
- So, 63/12 + 42/21 = 29/4
In mixed form: 71/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 63/12+84/21 63/24+42/21 63/36+42/21 63/12+42/63 63/60+42/21 63/84+42/21