Subtract 15/12 from 42/84
1st number: 42/84, 2nd number: 1 3/12
42/84 - 15/12 is -3/4.
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,
15/12 = 15 × 7/12 × 7 = 105/84 - Subtract the two like fractions:
42/84 - 105/84 = 42 - 105/84 = -63/84 - After reducing the fraction, the answer is -3/4
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