Question 11

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:

Solution

Number of electronics engineers initially = $$\frac{2}{3}\times\ 252\ =\ 168$$
So number of computer engineers initially = 252-168 =84
Now number of computer engineers recruited to make ratio 1:1 = 168-84 =84
Let average age of computer engineers be x
so total age will be 168x
Now average age of electronics engineers will be : x+2
So total age will be : (x+2) 168
Now as per given
Total age = 336(22)
Equating we get :
336(22) = 336(x+1)
we get x=21
so B and C are correct