Add 21/42 and 98/54, Solve 21/42 + 1 44/54 as a fraction

Add 21/42 and 98/54

1^st number: 21/42, 2^nd number: 1 44/54

21/42 + 98/54 is 125/54.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 42 × 9 = 378,
21/42 = 21 × 9/42 × 9 = 189/378
Likewise, for the 2nd fraction, since 54 × 7 = 378,
98/54 = 98 × 7/54 × 7 = 686/378
Add the two like fractions:
189/378 + 686/378 = 189 + 686/378 = 875/378
875/378 simplified gives 125/54
So, 21/42 + 98/54 = 125/54
In mixed form: 217/54

MathStep (Works offline)

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