Answers

Subtract 42/45 from 4/81

4/81 - 42/45 is -358/405.

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,
   4/81 = 4 × 5/81 × 5 = 20/405
3. Likewise, for the 2nd fraction, since 45 × 9 = 405,
   42/45 = 42 × 9/45 × 9 = 378/405
4. Subtract the two like fractions:
   20/405 - 378/405 = 20 - 378/405 = -358/405

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