THE CORRECT ANSWER IS (C). YOU CAN DETERMINE THE AVERAGE OF A, B,...

18. The correct answer is (C). You can determine the average of a, b, and c if you know

their sum. Statement (1) alone tells you that the sum of a and b is 10, but it provides no

information to help you determine the value of c. Statement (2) alone tells you nothing

about the value of either a or b, but it provides the value of c. Together, the two

statements allow you to determine the sum of the three terms (10

1

9) and in turn their

mean:

10

1

9

3

5

19