Subtract 80/42 from 18/12
1st number: 1 6/12, 2nd number: 1 38/42
18/12 - 80/42 is -17/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 12 and 42 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 12 × 7 = 84,
18/12 = 18 × 7/12 × 7 = 126/84 - Likewise, for the 2nd fraction, since 42 × 2 = 84,
80/42 = 80 × 2/42 × 2 = 160/84 - Subtract the two like fractions:
126/84 - 160/84 = 126 - 160/84 = -34/84 - After reducing the fraction, the answer is -17/42
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