Subtract 35/80 from 7/42, Solve 7/42

Subtract 35/80 from 7/42

7/42 - 35/80 is -13/48.

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,
7/42 = 7 × 40/42 × 40 = 280/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
35/80 = 35 × 21/80 × 21 = 735/1680
Subtract the two like fractions:
280/1680 - 735/1680 = 280 - 735/1680 = -455/1680
After reducing the fraction, the answer is -13/48

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