Subtract 18/21 from 54/80, Solve 54/80

Subtract 18/21 from 54/80

54/80 - 18/21 is -51/280.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 21 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
54/80 = 54 × 21/80 × 21 = 1134/1680
Likewise, for the 2nd fraction, since 21 × 80 = 1680,
18/21 = 18 × 80/21 × 80 = 1440/1680
Subtract the two like fractions:
1134/1680 - 1440/1680 = 1134 - 1440/1680 = -306/1680
After reducing the fraction, the answer is -51/280

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