Add 21/24 and 25/7, Solve 21/24 + 3 4/7 as a fraction

Add 21/24 and 25/7

1^st number: 21/24, 2^nd number: 3 4/7

21/24 + 25/7 is 249/56.

Find the least common denominator or LCM of the two denominators:
LCM of 24 and 7 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 24 × 7 = 168,
21/24 = 21 × 7/24 × 7 = 147/168
Likewise, for the 2nd fraction, since 7 × 24 = 168,
25/7 = 25 × 24/7 × 24 = 600/168
Add the two like fractions:
147/168 + 600/168 = 147 + 600/168 = 747/168
747/168 simplified gives 249/56
So, 21/24 + 25/7 = 249/56
In mixed form: 425/56

MathStep (Works offline)

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