Q) If a set contains n elements and A and B are the subsets of that set, then find the probability that A intersection B is = n .

A)
For the given condition, A should have all n elements and B too should have all n elements.
Total number of subsets = 2^n
Prob. of selecting subset having all n elements = 1/2^n
so Prob. of selecting 2 subsets (sequentially) both having n elements = (1/2^n)*(1/2^n)
= 1 / 2^2n

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