Question

Find the number of subsets and proper subsets of the following set:

A = {3, 4, 5, 6, 7}

Answer 1

The number of subsets = 256 
no. of proper subsets = 255

we find number of no of subset = 2^n, where n is the no. of elements in the set.

Answer 2

To find number of no of subset =  $2^{n}$
where n is the no. of elements in the set.
The number of subsets =$2^{5}$ =  32
no. of proper subsets = total subsets - null set = 32 - 1 = 31