Answers

Subtract 20/81 from 2/45

2/45 - 20/81 is -82/405.

Steps for subtracting fractions

1. 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
2. For the 1st fraction, since 45 × 9 = 405,
   2/45 = 2 × 9/45 × 9 = 18/405
3. Likewise, for the 2nd fraction, since 81 × 5 = 405,
   20/81 = 20 × 5/81 × 5 = 100/405
4. Subtract the two like fractions:
   18/405 - 100/405 = 18 - 100/405 = -82/405

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