Subtract 25/42 from 20/80
20/80 - 25/42 is -29/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 42 is 1680
Next, find the equivalent fraction of both fractional numbers with denominator 1680 - For the 1st fraction, since 80 × 21 = 1680,
20/80 = 20 × 21/80 × 21 = 420/1680 - Likewise, for the 2nd fraction, since 42 × 40 = 1680,
25/42 = 25 × 40/42 × 40 = 1000/1680 - Subtract the two like fractions:
420/1680 - 1000/1680 = 420 - 1000/1680 = -580/1680 - After reducing the fraction, the answer is -29/84
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