Subtract 40/80 from 5/42
5/42 - 40/80 is -8/21.
Steps for subtracting fractions
- 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,
5/42 = 5 × 40/42 × 40 = 200/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
40/80 = 40 × 21/80 × 21 = 840/1680 - Subtract the two like fractions:
200/1680 - 840/1680 = 200 - 840/1680 = -640/1680 - After reducing the fraction, the answer is -8/21
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