Question

If A ={X: X is a perfect square less than 100} then the number of subsets of A is:
(a) 1023
(b) 1022
(C) 511
(d) 510

Solution?

Answer 1

A : {1,4,9,16,25,36,49,64,81}

n(A) =9

so,

Proper Sunsets -->2^9 -1

=512-1

=511