Subtract 63/72 from 21/28
21/28 - 63/72 is -1/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 28 × 18 = 504,
21/28 = 21 × 18/28 × 18 = 378/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
63/72 = 63 × 7/72 × 7 = 441/504 - Subtract the two like fractions:
378/504 - 441/504 = 378 - 441/504 = -63/504 - After reducing the fraction, the answer is -1/8
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