Add 72/21 and 16/72, Solve 3 9/21 + 16/72 as a fraction

Add 72/21 and 16/72

1^st number: 3 9/21, 2^nd number: 16/72

72/21 + 16/72 is 230/63.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 21 × 24 = 504,
72/21 = 72 × 24/21 × 24 = 1728/504
Likewise, for the 2nd fraction, since 72 × 7 = 504,
16/72 = 16 × 7/72 × 7 = 112/504
Add the two like fractions:
1728/504 + 112/504 = 1728 + 112/504 = 1840/504
1840/504 simplified gives 230/63
So, 72/21 + 16/72 = 230/63
In mixed form: 341/63

MathStep (Works offline)

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