The average of 11 numbers is 42. The average of the first 6 numbers is 45 and…
2019
The average of 11 numbers is 42. The average of the first 6 numbers is 45 and the average of the last 6 numbers is 48. If the 6th number is excluded, what is the average of the remaining numbers?
- A.
36.6
- B.
38.8
- C.
43.6
- D.
46.5
Attempted by 116 students.
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Correct answer: A
Total of 11 numbers = 11×42 = 462 Sum of first 6 = 6×45 = 270 Sum of last 6 = 6×48 = 288 6th number counted twice, so: 6th number = 270 + 288 − 462 = 96 Remaining numbers = 10 numbers → sum = 462 − 96 = 366 Average = 366 ÷ 10 = 36.6