Add 84/15 and 80/21
1st number: 5 9/15, 2nd number: 3 17/21
84/15 + 80/21 is 988/105.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
84/15 = 84 × 7/15 × 7 = 588/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
80/21 = 80 × 5/21 × 5 = 400/105 - Add the two like fractions:
588/105 + 400/105 = 588 + 400/105 = 988/105 - So, 84/15 + 80/21 = 988/105
In mixed form: 943/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/30+80/21 84/15+80/42 84/45+80/21 84/15+80/63 84/75+80/21