Add 45/12 and 27/72, Solve 3 9/12 + 27/72 as a fraction

Add 45/12 and 27/72

1^st number: 3 9/12, 2^nd number: 27/72

45/12 + 27/72 is 33/8.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 72 is 72

Next, find the equivalent fraction of both fractional numbers with denominator 72
For the 1st fraction, since 12 × 6 = 72,
45/12 = 45 × 6/12 × 6 = 270/72
Likewise, for the 2nd fraction, since 72 × 1 = 72,
27/72 = 27 × 1/72 × 1 = 27/72
Add the two like fractions:
270/72 + 27/72 = 270 + 27/72 = 297/72
297/72 simplified gives 33/8
So, 45/12 + 27/72 = 33/8
In mixed form: 41/8

MathStep (Works offline)

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