Subtract 81/56 from 30/72, Solve 30/72

Subtract 81/56 from 30/72

1^st number: 30/72, 2^nd number: 1 25/56

30/72 - 81/56 is -173/168.

Find the least common denominator or LCM of the two denominators:
LCM of 72 and 56 is 504

Next, find the equivalent fraction of both fractional numbers with denominator 504
For the 1st fraction, since 72 × 7 = 504,
30/72 = 30 × 7/72 × 7 = 210/504
Likewise, for the 2nd fraction, since 56 × 9 = 504,
81/56 = 81 × 9/56 × 9 = 729/504
Subtract the two like fractions:
210/504 - 729/504 = 210 - 729/504 = -519/504
After reducing the fraction, the answer is -173/168

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