Add 18/27 and 21/45
18/27 + 21/45 is 17/15.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 45 is 135
Next, find the equivalent fraction of both fractional numbers with denominator 135 - For the 1st fraction, since 27 × 5 = 135,
18/27 = 18 × 5/27 × 5 = 90/135 - Likewise, for the 2nd fraction, since 45 × 3 = 135,
21/45 = 21 × 3/45 × 3 = 63/135 - Add the two like fractions:
90/135 + 63/135 = 90 + 63/135 = 153/135 - 153/135 simplified gives 17/15
- So, 18/27 + 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: 36/27+21/45 18/27+42/45 18/54+21/45 18/27+21/90 54/27+21/45 18/27+63/45 18/81+21/45 90/27+21/45