19 consecutive natural numbers are given. These numbers are in ascending order. The average of last 7 numbers is 25. What is the average of all 19 numbers?
Show answer & explanation
Correct answer: A
Explanation
Given:
19 consecutive natural numbers
Average of the last 7 numbers = 25
According to the formula:
For consecutive numbers, the average = the middle number
Average of the last 7 numbers = their middle number = 25
The middle (16th) number of the 7 numbers = 25
The middle (10th) number of the 19 numbers = 25 − 6 = 19