Add 10/42 and 21/24, Solve 10/42 + 21/24 as a fraction

Add 10/42 and 21/24

10/42 + 21/24 is 187/168.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 24 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 42 × 4 = 168,
10/42 = 10 × 4/42 × 4 = 40/168
Likewise, for the 2nd fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168
Add the two like fractions:
40/168 + 147/168 = 40 + 147/168 = 187/168
So, 10/42 + 21/24 = 187/168
In mixed form: 119/168

MathStep (Works offline)

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