The average age of A, B, and C is 20 years, and that of B and C is 25 years. What is the age of A?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e 10 years
The average age of A, B & C is 20 years.
⇒ (A + B + C) / 3 = 20
⇒ A + B + C = 60 ...(1)
The average age of B & C is 25 years.
⇒ (B + C) / 2 = 25
⇒ B + C = 50 ...(2)
Subtracting (2) from (1)
⇒ A + B + C - (B + C) = 60 - 50
⇒ A = 10 years