Subtract 81/72 from 7/28
1st number: 7/28, 2nd number: 1 9/72
7/28 - 81/72 is -7/8.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 28 and 72 is 504
Next, find the equivalent fraction of both fractional numbers with denominator 504 - For the 1st fraction, since 28 × 18 = 504,
7/28 = 7 × 18/28 × 18 = 126/504 - Likewise, for the 2nd fraction, since 72 × 7 = 504,
81/72 = 81 × 7/72 × 7 = 567/504 - Subtract the two like fractions:
126/504 - 567/504 = 126 - 567/504 = -441/504 - After reducing the fraction, the answer is -7/8
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