Answers

Subtract 20/36 from 4/81

4/81 - 20/36 is -41/81.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 36 is 324
   
   Next, find the equivalent fraction of both fractional numbers with denominator 324
2. For the 1st fraction, since 81 × 4 = 324,
   4/81 = 4 × 4/81 × 4 = 16/324
3. Likewise, for the 2nd fraction, since 36 × 9 = 324,
   20/36 = 20 × 9/36 × 9 = 180/324
4. Subtract the two like fractions:
   16/324 - 180/324 = 16 - 180/324 = -164/324
5. After reducing the fraction, the answer is -41/81

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