Add 21/28 and 28/18
1st number: 21/28, 2nd number: 1 10/18
21/28 + 28/18 is 83/36.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
28/18 = 28 × 14/18 × 14 = 392/252 - Add the two like fractions:
189/252 + 392/252 = 189 + 392/252 = 581/252 - 581/252 simplified gives 83/36
- So, 21/28 + 28/18 = 83/36
In mixed form: 211/36
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/28+28/18 21/28+56/18 21/56+28/18 21/28+28/36 63/28+28/18 21/28+84/18 21/84+28/18 21/28+28/54 21/28+28/90