Subtract 40/72 from 9/21
9/21 - 40/72 is -8/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 21 × 24 = 504,
9/21 = 9 × 24/21 × 24 = 216/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
40/72 = 40 × 7/72 × 7 = 280/504 - Subtract the two like fractions:
216/504 - 280/504 = 216 - 280/504 = -64/504 - After reducing the fraction, the answer is -8/63
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