Answers

Subtract 21/81 from 42/18

1^st number: 2 6/18, 2^nd number: 21/81

42/18 - 21/81 is 56/27.

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,
   42/18 = 42 × 9/18 × 9 = 378/162
3. Likewise, for the 2nd fraction, since 81 × 2 = 162,
   21/81 = 21 × 2/81 × 2 = 42/162
4. Subtract the two like fractions:
   378/162 - 42/162 = 378 - 42/162 = 336/162
5. After reducing the fraction, the answer is 56/27
6. In mixed form: 22/27

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