Subtract 81/72 from 15/21
1st number: 15/21, 2nd number: 1 9/72
15/21 - 81/72 is -23/56.
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,
15/21 = 15 × 24/21 × 24 = 360/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Subtract the two like fractions:
360/504 - 567/504 = 360 - 567/504 = -207/504 - After reducing the fraction, the answer is -23/56
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