Subtract 30/63 from 21/56
21/56 - 30/63 is -17/168.
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,
21/56 = 21 × 9/56 × 9 = 189/504 - Likewise, for the 2nd fraction, since 63 × 8 = 504,
30/63 = 30 × 8/63 × 8 = 240/504 - Subtract the two like fractions:
189/504 - 240/504 = 189 - 240/504 = -51/504 - After reducing the fraction, the answer is -17/168
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