Question

In a company there are 252 engineers, in which the ratio of the number of electronics engineers and computer engineers is 2 : 1. The ratio of the number of electronics engineers and computer engineers becomes 1:1 after recruitment of some more computer engineers. The average age of all the engineers is now 22 years and the average age of the computer engineers is 2 years less than the average age of electronics engineers.

(A) The average age (in years) of electronics engineers is 21 (B) The average age (in years) of computer engineers is 21 (C) The average age (in years) of electronics engineers is 23 (D) The average age (in years) of electronics engineers is 25 (E) The average age (in years) of computer engineers is 23

Choose the correct answer from the options given below:

Accepted Answer

B. Initially, electronics engineers = $252 	imes \frac{2}{3} = 168$, computer engineers = 84. After recruitment, ratio is 1:1, so computer engineers added = $168 - 84 = 84$. Total engineers = 336 (168 each). Let average age of computer engineers = $x$, then electronics engineers = $x + 2$. Total age = $168x + 168(x+2) = 336 	imes 22 \implies 168(2x+2) = 336 	imes 22 \implies 2x+2 = 44 \implies x = 21$. Average age of computer engineers = 21 (B), and electronics engineers = 23 (C). Hence, (B) and (C) only.

Engineers Ratio and Average Age

Explanation

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