Question
The average age of A and B is 22 years. If A is to be
replaced by C, the average would be 21 years. The average age of C and A is 23 years. Find the age of A.Solution
A + B = 2 × 22 = 44 yr. B + C = 2 × 21 = 42 yr. C + A = 2 × 23 = 46 yr. On adding all three, 2 (A + B + C) = 44 + 42 + 46 = 132 ⇒ A + B + C = 66 ∴ A = (A + B + C) – (B + C) = 66 – 42 = 24 yr.
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