Add 42/84 and 63/21
1st number: 42/84, 2nd number: 3 0/21
42/84 + 63/21 is 7/2.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
42/84 = 42 × 1/84 × 1 = 42/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
63/21 = 63 × 4/21 × 4 = 252/84 - Add the two like fractions:
42/84 + 252/84 = 42 + 252/84 = 294/84 - 294/84 simplified gives 7/2
- So, 42/84 + 63/21 = 7/2
In mixed form: 31/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/84+63/42