Answers

Subtract 20/45 from 5/81

5/81 - 20/45 is -31/81.

Steps for subtracting fractions

1. 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
2. For the 1st fraction, since 81 × 5 = 405,
   5/81 = 5 × 5/81 × 5 = 25/405
3. Likewise, for the 2nd fraction, since 45 × 9 = 405,
   20/45 = 20 × 9/45 × 9 = 180/405
4. Subtract the two like fractions:
   25/405 - 180/405 = 25 - 180/405 = -155/405
5. After reducing the fraction, the answer is -31/81

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