Add 21/12 and 3/8
1st number: 1 9/12, 2nd number: 3/8
21/12 + 3/8 is 17/8.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 8 is 24
Next, find the equivalent fraction of both fractional numbers with denominator 24 - For the 1st fraction, since 12 × 2 = 24,
21/12 = 21 × 2/12 × 2 = 42/24 - Likewise, for the 2nd fraction, since 8 × 3 = 24,
3/8 = 3 × 3/8 × 3 = 9/24 - Add the two like fractions:
42/24 + 9/24 = 42 + 9/24 = 51/24 - 51/24 simplified gives 17/8
- So, 21/12 + 3/8 = 17/8
In mixed form: 21/8
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/12+3/8 21/12+6/8 21/24+3/8 21/12+3/16 63/12+3/8 21/12+9/8 21/36+3/8 21/12+3/24 21/12+15/8 21/60+3/8 21/12+3/40 21/12+21/8 21/84+3/8 21/12+3/56