Add 21/12 and 3/5
1st number: 1 9/12, 2nd number: 3/5
21/12 + 3/5 is 47/20.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 5 is 60
Next, find the equivalent fraction of both fractional numbers with denominator 60 - For the 1st fraction, since 12 × 5 = 60,
21/12 = 21 × 5/12 × 5 = 105/60 - Likewise, for the 2nd fraction, since 5 × 12 = 60,
3/5 = 3 × 12/5 × 12 = 36/60 - Add the two like fractions:
105/60 + 36/60 = 105 + 36/60 = 141/60 - 141/60 simplified gives 47/20
- So, 21/12 + 3/5 = 47/20
In mixed form: 27/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12+3/5 21/12+6/5 21/24+3/5 21/12+3/10 63/12+3/5 21/12+9/5 21/36+3/5 21/12+3/15 21/12+15/5 21/60+3/5 21/12+3/25 21/12+21/5 21/84+3/5 21/12+3/35