Add 4/12 and 42/80, Solve 4/12 + 42/80 as a fraction

Add 4/12 and 42/80

4/12 + 42/80 is 103/120.

Find the least common denominator or LCM of the two denominators:
LCM of 12 and 80 is 240

Next, find the equivalent fraction of both fractional numbers with denominator 240
For the 1st fraction, since 12 × 20 = 240,
4/12 = 4 × 20/12 × 20 = 80/240
Likewise, for the 2nd fraction, since 80 × 3 = 240,
42/80 = 42 × 3/80 × 3 = 126/240
Add the two like fractions:
80/240 + 126/240 = 80 + 126/240 = 206/240
206/240 simplified gives 103/120
So, 4/12 + 42/80 = 103/120

MathStep (Works offline)

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