Add 18/21 and 45/42
1st number: 18/21, 2nd number: 1 3/42
18/21 + 45/42 is 27/14.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
18/21 = 18 × 2/21 × 2 = 36/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
45/42 = 45 × 1/42 × 1 = 45/42 - Add the two like fractions:
36/42 + 45/42 = 36 + 45/42 = 81/42 - 81/42 simplified gives 27/14
- So, 18/21 + 45/42 = 27/14
In mixed form: 113/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/21+45/42 18/21+90/42 18/42+45/42 18/21+45/84 54/21+45/42 18/63+45/42 90/21+45/42