Subtract 15/18 from 42/56
42/56 - 15/18 is -1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 18 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 56 × 9 = 504,
42/56 = 42 × 9/56 × 9 = 378/504 - Likewise, for the 2nd fraction, since 18 × 28 = 504,
15/18 = 15 × 28/18 × 28 = 420/504 - Subtract the two like fractions:
378/504 - 420/504 = 378 - 420/504 = -42/504 - After reducing the fraction, the answer is -1/12
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