Add 5/21 and 40/5, Solve 5/21 + 8 0/5 as a fraction

Add 5/21 and 40/5

1^st number: 5/21, 2^nd number: 8 0/5

5/21 + 40/5 is 173/21.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 5 is 105

Next, find the equivalent fraction of both fractional numbers with denominator 105
For the 1st fraction, since 21 × 5 = 105,
5/21 = 5 × 5/21 × 5 = 25/105
Likewise, for the 2nd fraction, since 5 × 21 = 105,
40/5 = 40 × 21/5 × 21 = 840/105
Add the two like fractions:
25/105 + 840/105 = 25 + 840/105 = 865/105
865/105 simplified gives 173/21
So, 5/21 + 40/5 = 173/21
In mixed form: 85/21

MathStep (Works offline)

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