Subtract 27/72 from 18/42
18/42 - 27/72 is 3/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 42 × 12 = 504,
18/42 = 18 × 12/42 × 12 = 216/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
27/72 = 27 × 7/72 × 7 = 189/504 - Subtract the two like fractions:
216/504 - 189/504 = 216 - 189/504 = 27/504 - After reducing the fraction, the answer is 3/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/42-27/72 18/42-54/72 18/84-27/72 54/42-27/72 18/42-81/72 90/42-27/72