The average of ages of 10 persons in a club was 32. What should be the age of…
2026
The average of ages of 10 persons in a club was 32. What should be the age of the new person joining in the club so as to increase the average by 4 ?
- A.
76
- B.
70
- C.
71
- D.
72
Attempted by 1150 students.
Show answer & explanation
Correct answer: A
Solution: Compute the totals and use the new average.
Total age of 10 persons = 10 × 32 = 320.
New average = 32 + 4 = 36.
Total age of 11 persons = 11 × 36 = 396.
Age of the new person = 396 − 320 = 76.
Shortcut: A direct formula is useful for similar problems.
Formula: Age of new person = original average + (number of existing persons + 1) × increase in average.
Apply values: 32 + (10 + 1) × 4 = 32 + 44 = 76.