Subtract 18/20 from 42/56
42/56 - 18/20 is -3/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 20 is 280
Next, find the equivalent fraction of both fractional numbers with denominator 280 - For the 1st fraction, since 56 × 5 = 280,
42/56 = 42 × 5/56 × 5 = 210/280 - Likewise, for the 2nd fraction, since 20 × 14 = 280,
18/20 = 18 × 14/20 × 14 = 252/280 - Subtract the two like fractions:
210/280 - 252/280 = 210 - 252/280 = -42/280 - After reducing the fraction, the answer is -3/20
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