Average age of a family of 4 members was 19 years, 4 years back. Birth of a…
2023
Average age of a family of 4 members was 19 years, 4 years back. Birth of a new child kept the average age of the family same even today. How old is the child today?
- A.
4 years
- B.
1 year
- C.
2 years
- D.
3 years
Attempted by 73 students.
Show answer & explanation
Correct answer: D
Key facts: average of family 4 years ago = 19 years.
Total age of the four members four years ago = 4 × 19 = 76 years.
After 4 years the same four members together add 4 × 4 = 16 years, so their total now = 76 + 16 = 92 years.
Let the child’s age today be x. There are now 5 members and the average today remains 19, so total ages today = 5 × 19 = 95 years. Therefore x = 95 − 92 = 3.
Final answer: The child is 3 years old today.