Add 36/21 and 27/54, Solve 1 15/21 + 27/54 as a fraction

Add 36/21 and 27/54

1^st number: 1 15/21, 2^nd number: 27/54

36/21 + 27/54 is 31/14.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 21 × 18 = 378,
36/21 = 36 × 18/21 × 18 = 648/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
27/54 = 27 × 7/54 × 7 = 189/378
Add the two like fractions:
648/378 + 189/378 = 648 + 189/378 = 837/378
837/378 simplified gives 31/14
So, 36/21 + 27/54 = 31/14
In mixed form: 23/14

MathStep (Works offline)

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