Civil Service Exam Reviewer · Averages · hard
The average of 11 numbers is 48. The average of the first 6 is 52, and the average of the last 6 is 53. What is the middle (6th) number?
- 48
- 53
- 108
- 102
Answer
D. 102
Solution
First 6 sum = 312; last 6 sum = 318. Together they count the middle number twice: 630 − 528 = 102.
More Averages questions
- The average age of 17 committee members increases by 2.5 years when a member aged 38 is replaced by a new member. How old is the new member?
- The average of 15 test scores was computed as 61. Later it was found that a score of 87 had been recorded as 102. What is the correct…
- The average of 8 consecutive even numbers is 23. What is the smallest of them?
- After 3 exams, Joy's average is 79. What score on the next exam would raise the average to exactly 80?
- The average of a, b and c is 79, and the average of a and b is 91. What is c?
- In a 10-item quiz, the scores and number of students were: 5 (7), 6 (3), 7 (6), 8 (8), 9 (1), 10 (4). What is the mean score?
- The average monthly salary of 8 employees is ₱20,000. When the manager's salary is included, the average rises by ₱500. What is the…
- The average of 3 consecutive odd numbers is 65. What is the largest of these numbers?
- In a contest, the highest and lowest of the judges' scores are dropped and the rest are averaged. The scores are 86, 84, 94, 96, 97, 73…
- The average of 7 numbers is 44. The average of the first 4 is 43, and the average of the last 4 is 43. What is the middle (4th) number?