GRE Sample Test 1 Quantitative Reasoning 2

Plug In the Answers, which are the possible values of x. Start with (C). Find the average of 6, 8, 10, and 23, which is 11.75, which is in the correct range. Eliminate (A) and (B) because the question asks for the greatest possible value of x. Next, try (D). The average of 6, 8, 10, and 28 is 13, which lies outside of the range. The correct answer is (C).