Add 84/18 and 45/12, Solve 4 12/18 + 3 9/12 as a fraction

Add 84/18 and 45/12

1^st number: 4 12/18, 2^nd number: 3 9/12

84/18 + 45/12 is 101/12.

Find the least common denominator or LCM of the two denominators:
LCM of 18 and 12 is 36

Next, find the equivalent fraction of both fractional numbers with denominator 36
For the 1st fraction, since 18 × 2 = 36,
84/18 = 84 × 2/18 × 2 = 168/36
Likewise, for the 2nd fraction, since 12 × 3 = 36,
45/12 = 45 × 3/12 × 3 = 135/36
Add the two like fractions:
168/36 + 135/36 = 168 + 135/36 = 303/36
303/36 simplified gives 101/12
So, 84/18 + 45/12 = 101/12
In mixed form: 85/12

MathStep (Works offline)

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