Question

Six friends, R, S, T, X, Y and Z, are sitting in a straight row facing north (but not necessarily in the same order). Only two people sit to the left of Y. Only two people sit between Y and Z. Only one person sits between Z and X. R sits to the immediate left of S. How many people sit between Y and S ?

• A. Two
• B. Three
• C. Zero
• D. One

Answer 1

Answer:

C. Zero

There are 0 (zero) people sitting between Y and S, as they are sitting immediately next to each other.

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Let's place the 6 friends in positions numbered 1 to 6 from left to right:

• Step 1: "Only two people sit to the left of Y."

  • This fixes Y at position 3.

  • _ _ Y _ _ _

• Step 2: "Only two people sit between Y and Z."

  • Since there are only two spots to the left of Y, Z must be placed to the right, leaving positions 4 and 5 empty. This fixes Z at position 6.

  • _ _ Y _ _ Z

• Step 3: "Only one person sits between Z and X."

  • Counting one spot to the left of Z (position 5), X must be placed at position 4.

  • _ _ Y X _ Z

• Step 4: "R sits to the immediate left of S."

  • We need two consecutive empty spaces for this pair. The only adjacent empty spaces left are positions 1 and 2. Therefore, R goes to position 1 and S goes to position 2.

  • R S Y X _ Z

• Step 5: Place the remaining person (T) in the last vacant spot (position 5).

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Final Row Configuration

Position	1	2	3	4	5	6
Friend	R	S	Y	X	T	Z

Since S is at position 2 and Y is at position 3, no one sits between them.