Bunuel
The median age of 15 children in group A was 12. The median age of 19 children in group B was 9. Two children - the youngest and the oldest - in group B were to group A. What was the new median age of the children in group A?1
(1) The youngest children in group B was 7 years old.
(2) The oldest child in group B was 12 years old.
Solution: Pre Analysis:- Median age of 15 children in group A was 12
- This means 8th child has age 12 in group A
- Median age of 19 children in group B was 9
- This means 10th child has age 9 in group B
- 2 children - the youngest and the oldest - in group B are sent to group A
- So, the median of group B doesn't change
- We are asked the new median of group A
Statement 1: The youngest children in group B was 7 years old
- This will be on the left of the old median of group A
- Now if the oldest child of group B is greater than 12, median of A doesn't change
- But if oldest child of group B is less than 12, median of A changes
- Thus, statement 1 alone is not sufficient and we can eliminate options A and D
Statement 2: The oldest child in group B was 12 years old
- Oldest child of B is median of A i.e., 12
- So, the median of A doesn't change and remain 12
- Because the middle term still remains 12
- Thus, statement 2 alone is sufficient
Hence the right answer is
Option B