After replacing an old member by a new member, it was found that the average age of five members of a club is the same as it was 3 years ago. What is the difference between the ages of the old and the new member?

After replacing an old member by a new member, it was found that the average age of five members of a club is the same as it was 3 years ago. What is the difference between the ages of the old and the new member?

A 15 yrs

B 8 yrs

C 4 yrs

D 2 yrs

Solution

Correct Answer: Option A

z= New member

x=old member

4 member+ x member=sum

4 member+ 12+z=sum

x=12+z

x+3=15+z

(x+3)-z=15