Add 42/21 and 3/90, Solve 2 0/21 + 3/90 as a fraction

Add 42/21 and 3/90

1^st number: 2 0/21, 2^nd number: 3/90

42/21 + 3/90 is 61/30.

Find the least common denominator or LCM of the two denominators:
LCM of 21 and 90 is 630

Next, find the equivalent fraction of both fractional numbers with denominator 630
For the 1st fraction, since 21 × 30 = 630,
42/21 = 42 × 30/21 × 30 = 1260/630
Likewise, for the 2nd fraction, since 90 × 7 = 630,
3/90 = 3 × 7/90 × 7 = 21/630
Add the two like fractions:
1260/630 + 21/630 = 1260 + 21/630 = 1281/630
1281/630 simplified gives 61/30
So, 42/21 + 3/90 = 61/30
In mixed form: 21/30

MathStep (Works offline)

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