Add 30/21 and 72/32, Solve 1 9/21 + 2 8/32 as a fraction

Add 30/21 and 72/32

1^st number: 1 9/21, 2^nd number: 2 8/32

30/21 + 72/32 is 103/28.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 32 is 672

Next, find the equivalent fraction of both fractional numbers with denominator 672
For the 1st fraction, since 21 × 32 = 672,
30/21 = 30 × 32/21 × 32 = 960/672
Likewise, for the 2nd fraction, since 32 × 21 = 672,
72/32 = 72 × 21/32 × 21 = 1512/672
Add the two like fractions:
960/672 + 1512/672 = 960 + 1512/672 = 2472/672
2472/672 simplified gives 103/28
So, 30/21 + 72/32 = 103/28
In mixed form: 319/28

MathStep (Works offline)

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