Subtract 54/72 from 18/42
18/42 - 54/72 is -9/28.
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,
54/72 = 54 × 7/72 × 7 = 378/504 - Subtract the two like fractions:
216/504 - 378/504 = 216 - 378/504 = -162/504 - After reducing the fraction, the answer is -9/28
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