Answers

Subtract 20/42 from 2/81

2/81 - 20/42 is -256/567.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 42 is 1134
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1134
2. For the 1st fraction, since 81 × 14 = 1134,
   2/81 = 2 × 14/81 × 14 = 28/1134
3. Likewise, for the 2nd fraction, since 42 × 27 = 1134,
   20/42 = 20 × 27/42 × 27 = 540/1134
4. Subtract the two like fractions:
   28/1134 - 540/1134 = 28 - 540/1134 = -512/1134
5. After reducing the fraction, the answer is -256/567

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