Add 40/84 and 42/21
1st number: 40/84, 2nd number: 2 0/21
40/84 + 42/21 is 52/21.
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,
40/84 = 40 × 1/84 × 1 = 40/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
42/21 = 42 × 4/21 × 4 = 168/84 - Add the two like fractions:
40/84 + 168/84 = 40 + 168/84 = 208/84 - 208/84 simplified gives 52/21
- So, 40/84 + 42/21 = 52/21
In mixed form: 210/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/84+42/21 40/84+84/21 40/84+42/63