Subtract 20/45 from 8/81
8/81 - 20/45 is -28/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
8/81 = 8 × 5/81 × 5 = 40/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
20/45 = 20 × 9/45 × 9 = 180/405 - Subtract the two like fractions:
40/405 - 180/405 = 40 - 180/405 = -140/405 - After reducing the fraction, the answer is -28/81
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