The average age of a group of 4 friends is 36 years. The youngest friend…
2024
The average age of a group of 4 friends is 36 years. The youngest friend amongst them is 6 years old. What was the average age of the other 3 friends at the time of the birth of the youngest friend?
- A.
40 years
- B.
42 years
- C.
36 years
- D.
38 years
Attempted by 1000 students.
Show answer & explanation
Correct answer: A
Step 1: Present total age
Average age of 4 friends = 36 years.
Total age now = 4 x 36 = 144 years.
Step 2: Go back 6 years
The youngest friend is 6 years old, so at the time of his birth we go back 6 years.
Total age of all 4 friends at that time = 144 - (4 x 6) = 144 - 24 = 120 years.
At that time the youngest friend was 0 years old, so 120 years is the combined age of the other 3 friends.
Step 3: Find the required average
Average age of the other 3 friends = 120 / 3 = 40 years.
Final Answer: 40 years.