Add 81/36 and 21/7
1st number: 2 9/36, 2nd number: 3 0/7
81/36 + 21/7 is 21/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 36 and 7 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 36 × 7 = 252,
81/36 = 81 × 7/36 × 7 = 567/252 - Likewise, for the 2nd fraction, since 7 × 36 = 252,
21/7 = 21 × 36/7 × 36 = 756/252 - Add the two like fractions:
567/252 + 756/252 = 567 + 756/252 = 1323/252 - 1323/252 simplified gives 21/4
- So, 81/36 + 21/7 = 21/4
In mixed form: 51/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/36+42/7 81/72+21/7 81/36+21/14 81/36+63/7 81/36+21/35 81/36+21/49