Let the set of four elements be {a, b, c, d}
To get the total amount of subsets contained in the set, we will find the power of the set. Given the set:
A = {a, b, c, d}
P(A) = 2^n
n is the number of element in the set
p(A) = 2^4
p(A) = 16
Hence the total subsets contained in the set is 16. Out of the subsets, the different subsets of 3 elements are:
{a, c, d}, {a, b, c} {a, b, d} and {b, c, d}
