Add 12/40 and 21/18
1st number: 12/40, 2nd number: 1 3/18
12/40 + 21/18 is 22/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 18 is 360
Next, find the equivalent fraction of both fractional numbers with denominator 360 - For the 1st fraction, since 40 × 9 = 360,
12/40 = 12 × 9/40 × 9 = 108/360 - Likewise, for the 2nd fraction, since 18 × 20 = 360,
21/18 = 21 × 20/18 × 20 = 420/360 - Add the two like fractions:
108/360 + 420/360 = 108 + 420/360 = 528/360 - 528/360 simplified gives 22/15
- So, 12/40 + 21/18 = 22/15
In mixed form: 17/15
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/40+21/18 12/40+42/18 12/80+21/18 12/40+21/36 36/40+21/18 12/40+63/18 12/40+21/54 60/40+21/18 12/40+21/90 84/40+21/18