CAT 2017 Slot 2 — QA Question 6
Change in AverageEasy
The average height of 22 toddlers increases by 2 inches when two of them leave this group. If the average height of these two toddlers is one-third the average height of the original 22, then the average height, in inches, of the remaining 20 toddlers is
Answer & solution
- A
30
- B
28
32
- D
26
Solution
Let the average height of 22 toddlers be ‘x’ inches.
Now as the average height of the 2 toddlers who leave the group is one-third the average height of the entire group 22, their average = x/3 inches.
Further, the average height of the balance 20 toddlers in terms of x will be ‘x + 2’ inches. So the average height of all 22 toddlers can be expressed as
x =
Hence, 22x = 2x/3 + 20x + 40
⇒ x = 30
So the average height of the balance
20 toddlers will be 30 + 2 or 32 inches.
Hence, option (c).