Add 12/21 and 27/18
1st number: 12/21, 2nd number: 1 9/18
12/21 + 27/18 is 29/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
12/21 = 12 × 6/21 × 6 = 72/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
27/18 = 27 × 7/18 × 7 = 189/126 - Add the two like fractions:
72/126 + 189/126 = 72 + 189/126 = 261/126 - 261/126 simplified gives 29/14
- So, 12/21 + 27/18 = 29/14
In mixed form: 21/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/21+27/18 12/21+54/18 12/42+27/18 12/21+27/36 36/21+27/18 12/21+81/18 12/63+27/18 12/21+27/54 60/21+27/18 12/21+27/90 84/21+27/18