Question

A is a set containing n elements. A subset P of A is chosen. The set A is reconstructed by replacing the elements of P. A subset Q of A is again chosen. The number of ways of choosing P and Q so that P  Q = Ï• is

Solution

Correct option is

      

For ai ∈ A, we have the following choice: 

   

Out of these only (ii), (iii) and (iv) imply .  

Therefore, the number of required subset is 3n.

SIMILAR QUESTIONS

Q1

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Q2

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Q4

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Q5

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Q6

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Q7

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Q8

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Q9

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Q10

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