Subtract 18/21 from 45/56, Solve 45/56

Subtract 18/21 from 45/56

45/56 - 18/21 is -3/56.

Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168

Next, find the equivalent fraction of both fractional numbers with denominator 168
For the 1st fraction, since 56 × 3 = 168,
45/56 = 45 × 3/56 × 3 = 135/168
Likewise, for the 2nd fraction, since 21 × 8 = 168,
18/21 = 18 × 8/21 × 8 = 144/168
Subtract the two like fractions:
135/168 - 144/168 = 135 - 144/168 = -9/168
After reducing the fraction, the answer is -3/56

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