Subtract 18/21 from 9/72
9/72 - 18/21 is -41/56.
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,
9/72 = 9 × 7/72 × 7 = 63/504 - Likewise, for the 2nd fraction, since 21 × 24 = 504,
18/21 = 18 × 24/21 × 24 = 432/504 - Subtract the two like fractions:
63/504 - 432/504 = 63 - 432/504 = -369/504 - After reducing the fraction, the answer is -41/56
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