Subtract 9/21 from 8/72
8/72 - 9/21 is -20/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 21 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 72 × 7 = 504,
8/72 = 8 × 7/72 × 7 = 56/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
9/21 = 9 × 24/21 × 24 = 216/504 - Subtract the two like fractions:
56/504 - 216/504 = 56 - 216/504 = -160/504 - After reducing the fraction, the answer is -20/63
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