Subtract 81/72 from 1/7, Solve 1/7 - 1 9/72 as a fraction

Subtract 81/72 from 1/7

1^st number: 1/7, 2^nd number: 1 9/72

1/7 - 81/72 is -55/56.

Find the least common denominator or LCM of the two denominators:
LCM of 7 and 72 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 7 × 72 = 504,
1/7 = 1 × 72/7 × 72 = 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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