Subtract 9/42 from 18/80, Solve 18/80

Subtract 9/42 from 18/80

18/80 - 9/42 is 3/280.

Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 80 × 21 = 1680,
18/80 = 18 × 21/80 × 21 = 378/1680
Likewise, for the 2nd fraction, since 42 × 40 = 1680,
9/42 = 9 × 40/42 × 40 = 360/1680
Subtract the two like fractions:
378/1680 - 360/1680 = 378 - 360/1680 = 18/1680
After reducing the fraction, the answer is 3/280

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