Subtract 36/80 from 18/42
18/42 - 36/80 is -3/140.
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,
18/42 = 18 × 40/42 × 40 = 720/1680 - Likewise, for the 2nd fraction, since 80 × 21 = 1680,
36/80 = 36 × 21/80 × 21 = 756/1680 - Subtract the two like fractions:
720/1680 - 756/1680 = 720 - 756/1680 = -36/1680 - After reducing the fraction, the answer is -3/140
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