Answers

Subtract 10/21 from 81/2

1^st number: 40 1/2, 2^nd number: 10/21

81/2 - 10/21 is 1681/42.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 2 and 21 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 2 × 21 = 42,
   81/2 = 81 × 21/2 × 21 = 1701/42
3. Likewise, for the 2nd fraction, since 21 × 2 = 42,
   10/21 = 10 × 2/21 × 2 = 20/42
4. Subtract the two like fractions:
   1701/42 - 20/42 = 1701 - 20/42 = 1681/42
5. In mixed form: 401/42

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