Add 84/21 and 81/36
1st number: 4 0/21, 2nd number: 2 9/36
84/21 + 81/36 is 25/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 36 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 21 × 12 = 252,
84/21 = 84 × 12/21 × 12 = 1008/252 - Likewise, for the 2nd fraction, since 36 × 7 = 252,
81/36 = 81 × 7/36 × 7 = 567/252 - Add the two like fractions:
1008/252 + 567/252 = 1008 + 567/252 = 1575/252 - 1575/252 simplified gives 25/4
- So, 84/21 + 81/36 = 25/4
In mixed form: 61/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/42+81/36 84/21+81/72 84/63+81/36