Subtract 42/56 from 21/84
21/84 - 42/56 is -1/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 56 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 84 × 2 = 168,
21/84 = 21 × 2/84 × 2 = 42/168 - Likewise, for the 2nd fraction, since 56 × 3 = 168,
42/56 = 42 × 3/56 × 3 = 126/168 - Subtract the two like fractions:
42/168 - 126/168 = 42 - 126/168 = -84/168 - After reducing the fraction, the answer is -1/2
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