Subtract 30/42 from 30/81
30/81 - 30/42 is -65/189.
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,
30/81 = 30 × 14/81 × 14 = 420/1134 - Likewise, for the 2nd fraction, since 42 × 27 = 1134,
30/42 = 30 × 27/42 × 27 = 810/1134 - Subtract the two like fractions:
420/1134 - 810/1134 = 420 - 810/1134 = -390/1134 - After reducing the fraction, the answer is -65/189
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