Answers

Subtract 40/6 from 81/21

1^st number: 3 18/21, 2^nd number: 6 4/6

81/21 - 40/6 is -59/21.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 6 is 42
   
   Next, find the equivalent fraction of both fractional numbers with denominator 42
2. For the 1st fraction, since 21 × 2 = 42,
   81/21 = 81 × 2/21 × 2 = 162/42
3. Likewise, for the 2nd fraction, since 6 × 7 = 42,
   40/6 = 40 × 7/6 × 7 = 280/42
4. Subtract the two like fractions:
   162/42 - 280/42 = 162 - 280/42 = -118/42
5. After reducing the fraction, the answer is -59/21

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