Subtract 21/63 from 18/56
18/56 - 21/63 is -1/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 63 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 56 × 9 = 504,
18/56 = 18 × 9/56 × 9 = 162/504 - Likewise, for the 2nd fraction, since 63 × 8 = 504,
21/63 = 21 × 8/63 × 8 = 168/504 - Subtract the two like fractions:
162/504 - 168/504 = 162 - 168/504 = -6/504 - After reducing the fraction, the answer is -1/84
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