Seven students Q, R, S T, W, X and Y are sitting in a straight row facing north.

Step-by-step arrangement 

We have 7 students: Q, R, S, T, W, X, Y
They are sitting in a row facing north.

Step 1: Fix R (R को fix करें)

• “No one is sitting to the left of R”👉 R is at position 1 (extreme left)

Step 2: Place T

• “Only four students are sitting between R and T”👉 Positions: R _ _ _ _ T👉 So, T is at position 6

Step 3: Place Y

• “Only three students are sitting to the right of Y”👉 So, Y is at position 4

Step 4: Place X and S

• “X is immediate left of S”👉 Possible pairs: (2,3), (3,4), (4,5), (5,6), (6,7)

But:

• Position 4 = Y (fixed) ❌
• Position 6 = T (fixed) ❌

👉 Valid position: 2 (X), 3 (S)

Step 5: Place W

• “W is not immediate neighbour of Y”👉 Y is at position 4 → neighbours = 3 and 5👉 So W cannot be at 3 or 5

Remaining positions: 5 and 7
👉 W = 7

Final arrangement:

Step 6: Count between W and Y

• Y = position 4
• W = position 7

Students between them: positions 5, 6 → 2 students

Final Answer:

✅ Two / दो