Add 21/3 and 45/12
1st number: 7 0/3, 2nd number: 3 9/12
21/3 + 45/12 is 43/4.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 3 and 12 is 12
Next, find the equivalent fraction of both fractional numbers with denominator 12 - For the 1st fraction, since 3 × 4 = 12,
21/3 = 21 × 4/3 × 4 = 84/12 - Likewise, for the 2nd fraction, since 12 × 1 = 12,
45/12 = 45 × 1/12 × 1 = 45/12 - Add the two like fractions:
84/12 + 45/12 = 84 + 45/12 = 129/12 - 129/12 simplified gives 43/4
- So, 21/3 + 45/12 = 43/4
In mixed form: 103/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/3+45/12 21/3+90/12 21/6+45/12 21/3+45/24 63/3+45/12 21/9+45/12 21/3+45/36 21/15+45/12 21/3+45/60 21/3+45/84