Civil Service Exam Reviewer · Averages · hard
The average of 11 numbers is 50. The average of the first 6 is 48, and the average of the last 6 is 53. What is the middle (6th) number?
- 50
- 51
- 62
- 56
Answer
D. 56
Solution
First 6 sum = 288; last 6 sum = 318. Together they count the middle number twice: 606 − 550 = 56.
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