Reasoning : Logical Reasoning & Analytical Ability

Q 266 / 325

UPSC CSE Prelims 2013

A tennis coach is trying to put together a team of four players for the forthcoming tournament. For this, 7 players are available: males A, B and C; and females W, X, Y and Z. All players have equal capability and at least two males will be there in the team. For a team of four, all players must be able to play with each other. But B cannot play with W, C cannot play with Z and W cannot play with Y.
If B is selected and Y is rejected, the team will consist of which one of the following groups?

EXPLANATION

Correct Option (C)

Given that B is selected and Y is rejected. According to the problem statement, B cannot play with W. Therefore, if B is selected, W must be rejected from the team.

The available players are A, B, C (males) and W, X, Y, Z (females).

Based on the conditions:

  • B is selected.
  • Y is rejected.
  • W is rejected (because B is selected).

The players remaining for selection are A, C (males) and X, Z (females). We need to select 3 more players to form a team of four.

The team must have at least two males. Since B is already selected, we need to select at least one more male from A or C.

Let us consider selecting both remaining males, A and C. This forms a core of three males (A, B, C), satisfying the "at least two males" condition.

Now, one more player is needed from the remaining females (X, Z).

The problem states that C cannot play with Z. Since C is part of our selected core (A, B, C), Z cannot be selected as the fourth player.

Therefore, the only eligible female remaining is X.

The resulting team is A, B, C, X.

This team satisfies all conditions:

  • It has four players.
  • It has three males (A, B, C), fulfilling the "at least two males" requirement.
  • All player conflicts are avoided: B is not with W, C is not with Z, and W is not with Y (as W and Y are not in the team).

Incorrect Options:

The initial conditions are: B is selected, Y is rejected.

Option (A) A, B, C and W:

  • This option includes W. However, the problem states that B cannot play with W. Since B is selected, W cannot be part of the team.

Option (B) A, B, C and Z:

  • This option includes C and Z. However, the problem states that C cannot play with Z. Therefore, C and Z cannot be in the same team.

Option (D) A, W, Y and Z:

  • This option violates the initial conditions: B is selected, but not included in this option. Y is rejected, but included in this option. W is rejected (due to B's selection), but included in this option.
  • Additionally, W cannot play with Y, and both are present in this option, creating another conflict.