Average - Quantitative Aptitude (MCQ) questions for Q. 780
Q. If from a group of 5 people, an old member is replaced by a new one, the average age is same as it was 3 years ago. What is the difference between the ages of the old member and the new one?- Published on 06 Jul 15a. 12
b. 15
c. 11
d. 18
ANSWER: 15
The present average age is (x + 3) when the old member is present and it equals to x when an old member is replaced by a new one.
The difference in the ages of the old member and the new one is equal to the difference in the total age before and after the replacement = 15 years.