AMC 8 1991 Problem 11

There are several sets of three different numbers whose sum is $15$ which can be chosen from $\{ 1,2,3,4,5,6,7,8,9 \}$. How many of these sets contain a $5$? $\text{(A)}\ 3 \text{(B)}\ 4 \text{(C)}\ 5 \text{(D)}\ 6 \text{(E)}\ 7$