Subtract 15/18 from 20/56
20/56 - 15/18 is -10/21.
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,
20/56 = 20 × 9/56 × 9 = 180/504 - Likewise, for the 2nd fraction, since 18 × 28 = 504,
15/18 = 15 × 28/18 × 28 = 420/504 - Subtract the two like fractions:
180/504 - 420/504 = 180 - 420/504 = -240/504 - After reducing the fraction, the answer is -10/21
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