Subtract 10/80 from 12/42, Solve 12/42

Subtract 10/80 from 12/42

12/42 - 10/80 is 9/56.

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

Next, find the equivalent fraction of both fractional numbers with denominator 1680
For the 1st fraction, since 42 × 40 = 1680,
12/42 = 12 × 40/42 × 40 = 480/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
10/80 = 10 × 21/80 × 21 = 210/1680
Subtract the two like fractions:
480/1680 - 210/1680 = 480 - 210/1680 = 270/1680
After reducing the fraction, the answer is 9/56

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