Add 40/3 and 21/42, Solve 13 1/3 + 21/42 as a fraction

Add 40/3 and 21/42

1^st number: 13 1/3, 2^nd number: 21/42

40/3 + 21/42 is 83/6.

Find the least common denominator or LCM of the two denominators:
LCM of 3 and 42 is 42

Next, find the equivalent fraction of both fractional numbers with denominator 42
For the 1st fraction, since 3 × 14 = 42,
40/3 = 40 × 14/3 × 14 = 560/42
Likewise, for the 2nd fraction, since 42 × 1 = 42,
21/42 = 21 × 1/42 × 1 = 21/42
Add the two like fractions:
560/42 + 21/42 = 560 + 21/42 = 581/42
581/42 simplified gives 83/6
So, 40/3 + 21/42 = 83/6
In mixed form: 135/6

MathStep (Works offline)

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