Add 8/12 and 21/45
8/12 + 21/45 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 45 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 12 × 15 = 180,
8/12 = 8 × 15/12 × 15 = 120/180 - Likewise, for the 2nd fraction, since 45 × 4 = 180,
21/45 = 21 × 4/45 × 4 = 84/180 - Add the two like fractions:
120/180 + 84/180 = 120 + 84/180 = 204/180 - 204/180 simplified gives 17/15
- So, 8/12 + 21/45 = 17/15
In mixed form: 12/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/12+21/45 8/12+42/45 8/24+21/45 8/12+21/90 24/12+21/45 8/12+63/45 8/36+21/45 40/12+21/45 8/60+21/45 56/12+21/45 8/84+21/45