Add 81/84 and 30/15
1st number: 81/84, 2nd number: 2 0/15
81/84 + 30/15 is 83/28.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 15 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
81/84 = 81 × 5/84 × 5 = 405/420 - Likewise, for the 2nd fraction, since 15 × 28 = 420,
30/15 = 30 × 28/15 × 28 = 840/420 - Add the two like fractions:
405/420 + 840/420 = 405 + 840/420 = 1245/420 - 1245/420 simplified gives 83/28
- So, 81/84 + 30/15 = 83/28
In mixed form: 227/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/84+60/15 81/84+90/15 81/84+30/45 81/84+30/75