Question

A is a set containing n elements A subset P of A is chosen at random. The set A is reconstructed by replacing the elements of P. A subset Q of A is again chosen at random. The probalility that P and Q have no common elements is 

(a) \(\left(\frac 34\right)^n\)

(b) \(\left(\frac 12\right)^n\)

(c) \(\frac{^nC_2}{2^n}\)

(d) None of these

Answer 1

Correct option is (a) \(\left(\frac 34\right)^n\)