Subtract 42/81 from 12/24
12/24 - 42/81 is -1/54.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 24 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 24 × 27 = 648,
12/24 = 12 × 27/24 × 27 = 324/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
42/81 = 42 × 8/81 × 8 = 336/648 - Subtract the two like fractions:
324/648 - 336/648 = 324 - 336/648 = -12/648 - After reducing the fraction, the answer is -1/54
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