Add 75/54 and 4/21, Solve 1 21/54 + 4/21 as a fraction

Add 75/54 and 4/21

1^st number: 1 21/54, 2^nd number: 4/21

75/54 + 4/21 is 199/126.

Find the least common denominator or LCM of the two denominators:
LCM of 54 and 21 is 378

Next, find the equivalent fraction of both fractional numbers with denominator 378
For the 1st fraction, since 54 × 7 = 378,
75/54 = 75 × 7/54 × 7 = 525/378
Likewise, for the 2nd fraction, since 21 × 18 = 378,
4/21 = 4 × 18/21 × 18 = 72/378
Add the two like fractions:
525/378 + 72/378 = 525 + 72/378 = 597/378
597/378 simplified gives 199/126
So, 75/54 + 4/21 = 199/126
In mixed form: 173/126

MathStep (Works offline)

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