Answers

Subtract 42/18 from 20/81

1^st number: 20/81, 2^nd number: 2 6/18

20/81 - 42/18 is -169/81.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 18 is 162
   
   Next, find the equivalent fraction of both fractional numbers with denominator 162
2. For the 1st fraction, since 81 × 2 = 162,
   20/81 = 20 × 2/81 × 2 = 40/162
3. Likewise, for the 2nd fraction, since 18 × 9 = 162,
   42/18 = 42 × 9/18 × 9 = 378/162
4. Subtract the two like fractions:
   40/162 - 378/162 = 40 - 378/162 = -338/162
5. After reducing the fraction, the answer is -169/81

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