Add 42/18 and 21/28, Solve 2 6/18 + 21/28 as a fraction

Add 42/18 and 21/28

1^st number: 2 6/18, 2^nd number: 21/28

42/18 + 21/28 is 37/12.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 28 is 252

Next, find the equivalent fraction of both fractional numbers with denominator 252
For the 1st fraction, since 18 × 14 = 252,
42/18 = 42 × 14/18 × 14 = 588/252
Likewise, for the 2nd fraction, since 28 × 9 = 252,
21/28 = 21 × 9/28 × 9 = 189/252
Add the two like fractions:
588/252 + 189/252 = 588 + 189/252 = 777/252
777/252 simplified gives 37/12
So, 42/18 + 21/28 = 37/12
In mixed form: 31/12

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad