Add 5/12 and 21/7, Solve 5/12 + 3 0/7 as a fraction

Add 5/12 and 21/7

1^st number: 5/12, 2^nd number: 3 0/7

5/12 + 21/7 is 41/12.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 7 is 84

Next, find the equivalent fraction of both fractional numbers with denominator 84
For the 1st fraction, since 12 × 7 = 84,
5/12 = 5 × 7/12 × 7 = 35/84
Likewise, for the 2nd fraction, since 7 × 12 = 84,
21/7 = 21 × 12/7 × 12 = 252/84
Add the two like fractions:
35/84 + 252/84 = 35 + 252/84 = 287/84
287/84 simplified gives 41/12
So, 5/12 + 21/7 = 41/12
In mixed form: 35/12

MathStep (Works offline)

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