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