Subtract 63/80 from 18/42
18/42 - 63/80 is -201/560.
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,
63/80 = 63 × 21/80 × 21 = 1323/1680 - Subtract the two like fractions:
720/1680 - 1323/1680 = 720 - 1323/1680 = -603/1680 - After reducing the fraction, the answer is -201/560
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