Subtract 15/12 from 12/42
1st number: 12/42, 2nd number: 1 3/12
12/42 - 15/12 is -27/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 12 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
12/42 = 12 × 2/42 × 2 = 24/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
15/12 = 15 × 7/12 × 7 = 105/84 - Subtract the two like fractions:
24/84 - 105/84 = 24 - 105/84 = -81/84 - After reducing the fraction, the answer is -27/28
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