A set with n elements has 2n subsets. The number of proper subsets is one less, since 2n includes the set itself.
The empty set has only one subset: itself. It has no proper subsets.
6
An element doesn't have subsets. Sets can have subsets.
To find how many proper subsets there are in a set you can use the formula n^2 -n and if you would also like to find all subsets including improper the formula is n^2 -n +1
8 subsets
Only a set can have subsets, a number cannot have subsets.
5 subsets of 4 and of 1, 10 subsets of 3 and of 2 adds up to 30.
That means, figure out how many different subsets a set has. In general, if a set has n elements, it has 2n different subsets.
Two. The set {x} has the subsets {} and {x}.
512 subsets
If the universal set contains N elements then it has 2N subsets.