Add 15/18 and 42/72
15/18 + 42/72 is 17/12.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 72 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 18 × 4 = 72,
15/18 = 15 × 4/18 × 4 = 60/72 - Likewise, for the 2nd fraction, since 72 × 1 = 72,
42/72 = 42 × 1/72 × 1 = 42/72 - Add the two like fractions:
60/72 + 42/72 = 60 + 42/72 = 102/72 - 102/72 simplified gives 17/12
- So, 15/18 + 42/72 = 17/12
In mixed form: 15/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 30/18+42/72 15/18+84/72 15/36+42/72 45/18+42/72 15/54+42/72 75/18+42/72 15/90+42/72