Subtract 20/56 from 3/18
3/18 - 20/56 is -4/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 56 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 18 × 28 = 504,
3/18 = 3 × 28/18 × 28 = 84/504 - Likewise, for the 2nd fraction, since 56 × 9 = 504,
20/56 = 20 × 9/56 × 9 = 180/504 - Subtract the two like fractions:
84/504 - 180/504 = 84 - 180/504 = -96/504 - After reducing the fraction, the answer is -4/21
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