Subsets

This problem was answered before

 

There are 2^10 different subsets in the original set.

 

Now let us just subtract subsets without a 5

 

Let us just pretend you have set without a 5

 

So {1 2 3 4 6 7 8 9 10} Is your new set

 

So how many subsets can you make from that?

 

2^9 subsets

 

2^10 - 2^9 = 512 different subsets

 

NOTE: 2^10 - 2^9 is NOT 2.

 

So there you have it! :D:D:D