Assume that the set S has 14 elements.

Question

How many subsets of S have at most 4 elements?

Answer 1

null set --- 1
one element --- C(14,1) = 14
two elements --- C(14,2) = 91
three elements --- C(14,3) = 364
four elements --- C(14,4) = 1001

add them up.

Answer 2

^no, I just tried it and it isn't right. any other suggestions?

Answer 3

Got it:

C(14,0)+C(14,1)+C(14,3)+C(14,4)=answer

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