Answers

Subtract 7/45 from 7/81

7/81 - 7/45 is -28/405.

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,
   7/81 = 7 × 5/81 × 5 = 35/405
3. Likewise, for the 2nd fraction, since 45 × 9 = 405,
   7/45 = 7 × 9/45 × 9 = 63/405
4. Subtract the two like fractions:
   35/405 - 63/405 = 35 - 63/405 = -28/405

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