In a queue, Mr. X is fourteenth from the front and Mr. Y is seventeenth from the end, while Mr. Z is exactly in between Mr. X and Mr. Y. If Mr. X is ahead Mr. Y and there are 48 persons in the queue, how many persons are then between Mr. X and Mr. Z?
- A6
- B7
- C8Correct
- D9
Explanation
Here's a brief explanation:
-
Find Y's position from the front: Total persons = (Position from front) + (Position from end) - 1 48 = (Y's position from front) + 17 - 1 Y's position from front = 48 - 17 + 1 = 32nd.
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Find the number of persons between X and Y: Mr. X is 14th from the front. Mr. Y is 32nd from the front. Number of persons between X and Y = (Y's position from front) - (X's position from front) - 1 Number of persons between X and Y = 32 - 14 - 1 = 17 persons.
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Find the number of persons between X and Z: Mr. Z is exactly in between Mr. X and Mr. Y. If there are 17 persons between X and Y, and Z is the middle person among them, then Z divides these 17 persons into two equal groups, with Z himself being the central point. Let 'k' be the number of persons between X and Z. Then 'k' is also the number of persons between Z and Y. The total number of persons between X and Y can be represented as: k (persons between X and Z) + 1 (Mr. Z himself) + k (persons between Z and Y) = 2k + 1. We know 2k + 1 = 17. 2k = 16 k = 8. So, there are 8 persons between Mr. X and Mr. Z.
The final answer is C) 8.

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