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

Subtract 42/80 from 10/42

10/42 - 42/80 is -241/840.

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,
10/42 = 10 × 40/42 × 40 = 400/1680
Likewise, for the 2nd fraction, since 80 × 21 = 1680,
42/80 = 42 × 21/80 × 21 = 882/1680
Subtract the two like fractions:
400/1680 - 882/1680 = 400 - 882/1680 = -482/1680
After reducing the fraction, the answer is -241/840

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