Subtract 18/81 from 9/45
9/45 - 18/81 is -1/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
9/45 = 9 × 9/45 × 9 = 81/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
18/81 = 18 × 5/81 × 5 = 90/405 - Subtract the two like fractions:
81/405 - 90/405 = 81 - 90/405 = -9/405 - After reducing the fraction, the answer is -1/45
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