Subtract 18/6 from 81/42
1st number: 1 39/42, 2nd number: 3 0/6
81/42 - 18/6 is -15/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 6 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
81/42 = 81 × 1/42 × 1 = 81/42 - Likewise, for the 2nd fraction, since 6 × 7 = 42,
18/6 = 18 × 7/6 × 7 = 126/42 - Subtract the two like fractions:
81/42 - 126/42 = 81 - 126/42 = -45/42 - After reducing the fraction, the answer is -15/14
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