Add 12/42 and 27/20, Solve 12/42 + 1 7/20 as a fraction

Add 12/42 and 27/20

1^st number: 12/42, 2^nd number: 1 7/20

12/42 + 27/20 is 229/140.

Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420

Next, find the equivalent fraction of both fractional numbers with denominator 420
For the 1st fraction, since 42 × 10 = 420,
12/42 = 12 × 10/42 × 10 = 120/420
Likewise, for the 2nd fraction, since 20 × 21 = 420,
27/20 = 27 × 21/20 × 21 = 567/420
Add the two like fractions:
120/420 + 567/420 = 120 + 567/420 = 687/420
687/420 simplified gives 229/140
So, 12/42 + 27/20 = 229/140
In mixed form: 189/140

MathStep (Works offline)

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