Answers

Subtract 2/81 from 21/18

1^st number: 1 3/18, 2^nd number: 2/81

21/18 - 2/81 is 185/162.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 81 is 162
   
   Next, find the equivalent fraction of both fractional numbers with denominator 162
2. For the 1st fraction, since 18 × 9 = 162,
   21/18 = 21 × 9/18 × 9 = 189/162
3. Likewise, for the 2nd fraction, since 81 × 2 = 162,
   2/81 = 2 × 2/81 × 2 = 4/162
4. Subtract the two like fractions:
   189/162 - 4/162 = 189 - 4/162 = 185/162
5. In mixed form: 123/162

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