Subtract 18/42 from 81/56, Solve 1 25/56

Subtract 18/42 from 81/56

1^st number: 1 25/56, 2^nd number: 18/42

81/56 - 18/42 is 57/56.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 42 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
81/56 = 81 × 3/56 × 3 = 243/168
Likewise, for the 2nd fraction, since 42 × 4 = 168,
18/42 = 18 × 4/42 × 4 = 72/168
Subtract the two like fractions:
243/168 - 72/168 = 243 - 72/168 = 171/168
After reducing the fraction, the answer is 57/56
In mixed form: 11/56

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