Subtract 60/80 from 4/42, Solve 4/42

Subtract 60/80 from 4/42

4/42 - 60/80 is -55/84.

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,
4/42 = 4 × 40/42 × 40 = 160/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
60/80 = 60 × 21/80 × 21 = 1260/1680
Subtract the two like fractions:
160/1680 - 1260/1680 = 160 - 1260/1680 = -1100/1680
After reducing the fraction, the answer is -55/84

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