Subtract 18/12 from 15/42
1st number: 15/42, 2nd number: 1 6/12
15/42 - 18/12 is -8/7.
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,
15/42 = 15 × 2/42 × 2 = 30/84 - Likewise, for the 2nd fraction, since 12 × 7 = 84,
18/12 = 18 × 7/12 × 7 = 126/84 - Subtract the two like fractions:
30/84 - 126/84 = 30 - 126/84 = -96/84 - After reducing the fraction, the answer is -8/7
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