Add 27/20 and 42/21
1st number: 1 7/20, 2nd number: 2 0/21
27/20 + 42/21 is 67/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 20 and 21 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 20 × 21 = 420,
27/20 = 27 × 21/20 × 21 = 567/420 - Likewise, for the 2nd fraction, since 21 × 20 = 420,
42/21 = 42 × 20/21 × 20 = 840/420 - Add the two like fractions:
567/420 + 840/420 = 567 + 840/420 = 1407/420 - 1407/420 simplified gives 67/20
- So, 27/20 + 42/21 = 67/20
In mixed form: 37/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/20+42/21 27/20+84/21 27/40+42/21 81/20+42/21 27/60+42/21 27/20+42/63