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 ?
Answer Choices
A. 3
B. 4
C. 5
D. 6
E. 7
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 ?
Answer Choices
A. 3
B. 4
C. 5
D. 6
E. 7