Subtract 7/42 from 6/81
6/81 - 7/42 is -5/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 42 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 81 × 14 = 1134,
6/81 = 6 × 14/81 × 14 = 84/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
7/42 = 7 × 27/42 × 27 = 189/1134 - Subtract the two like fractions:
84/1134 - 189/1134 = 84 - 189/1134 = -105/1134 - After reducing the fraction, the answer is -5/54
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