Answers

Subtract 20/54 from 28/81

28/81 - 20/54 is -2/81.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 54 is 162
   
   Next, find the equivalent fraction of both fractional numbers with denominator 162
2. For the 1st fraction, since 81 × 2 = 162,
   28/81 = 28 × 2/81 × 2 = 56/162
3. Likewise, for the 2nd fraction, since 54 × 3 = 162,
   20/54 = 20 × 3/54 × 3 = 60/162
4. Subtract the two like fractions:
   56/162 - 60/162 = 56 - 60/162 = -4/162
5. After reducing the fraction, the answer is -2/81

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