Add 8/21 and 42/36, Solve 8/21 + 1 6/36 as a fraction

Add 8/21 and 42/36

1^st number: 8/21, 2^nd number: 1 6/36

8/21 + 42/36 is 65/42.

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,
8/21 = 8 × 12/21 × 12 = 96/252
Likewise, for the 2nd fraction, since 36 × 7 = 252,
42/36 = 42 × 7/36 × 7 = 294/252
Add the two like fractions:
96/252 + 294/252 = 96 + 294/252 = 390/252
390/252 simplified gives 65/42
So, 8/21 + 42/36 = 65/42
In mixed form: 123/42

MathStep (Works offline)

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