Add 36/8 and 20/21, Solve 4 4/8 + 20/21 as a fraction

Add 36/8 and 20/21

1^st number: 4 4/8, 2^nd number: 20/21

36/8 + 20/21 is 229/42.

Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 8 × 21 = 168,
36/8 = 36 × 21/8 × 21 = 756/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
20/21 = 20 × 8/21 × 8 = 160/168
Add the two like fractions:
756/168 + 160/168 = 756 + 160/168 = 916/168
916/168 simplified gives 229/42
So, 36/8 + 20/21 = 229/42
In mixed form: 519/42

MathStep (Works offline)

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