Subtract 10/12 from 42/84
42/84 - 10/12 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 84 × 1 = 84,
42/84 = 42 × 1/84 × 1 = 42/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
10/12 = 10 × 7/12 × 7 = 70/84 - Subtract the two like fractions:
42/84 - 70/84 = 42 - 70/84 = -28/84 - After reducing the fraction, the answer is -1/3
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