Subtract 20/42 from 28/84
28/84 - 20/42 is -1/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
28/84 = 28 × 1/84 × 1 = 28/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
20/42 = 20 × 2/42 × 2 = 40/84 - Subtract the two like fractions:
28/84 - 40/84 = 28 - 40/84 = -12/84 - After reducing the fraction, the answer is -1/7
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