Subtract 81/72 from 12/84
1st number: 12/84, 2nd number: 1 9/72
12/84 - 81/72 is -55/56.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 84 × 6 = 504,
12/84 = 12 × 6/84 × 6 = 72/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Subtract the two like fractions:
72/504 - 567/504 = 72 - 567/504 = -495/504 - After reducing the fraction, the answer is -55/56
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