Subtract 45/81 from 15/42
15/42 - 45/81 is -25/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 81 is 1134
Next, find the equivalent fraction of both fractional numbers with denominator 1134 - For the 1st fraction, since 42 × 27 = 1134,
15/42 = 15 × 27/42 × 27 = 405/1134 - Likewise, for the 2nd fraction, since 81 × 14 = 1134,
45/81 = 45 × 14/81 × 14 = 630/1134 - Subtract the two like fractions:
405/1134 - 630/1134 = 405 - 630/1134 = -225/1134 - After reducing the fraction, the answer is -25/126
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