Let n=number of entrees on the menu
A "family dinner" is an un-ordered 4-entree subset of the set of n entrees on the menu; thus:
C(n,4) =	n! 4! x (n-4)!	is the number of possible dinners

Using the above formula for various n:

C(4,4) = 1 C(5,4) = 5 C(6,4) = 15 C(7,4) = 35		C(8,4) = 70 C(9,4) = 126 C(10,4) = 210 C(11,4) = 330
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