Add 15/18 and 45/42
1st number: 15/18, 2nd number: 1 3/42
15/18 + 45/42 is 40/21.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 42 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
15/18 = 15 × 7/18 × 7 = 105/126 - Likewise, for the 2nd fraction, since 42 × 3 = 126,
45/42 = 45 × 3/42 × 3 = 135/126 - Add the two like fractions:
105/126 + 135/126 = 105 + 135/126 = 240/126 - 240/126 simplified gives 40/21
- So, 15/18 + 45/42 = 40/21
In mixed form: 119/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/18+45/42 15/18+90/42 15/36+45/42 15/18+45/84 45/18+45/42 15/54+45/42 75/18+45/42 15/90+45/42