Five men M, N, O, P and Q are sitting in a row facing north. M is sitting at one end and O is on the other end. Q sits to the immediate left of M and to the immediate right of P.  Who sits third to the right of O?

Q

Let the empty position be numbered 1 - 5,

1. M is sitting at one end. Q sits to the immediate left of M and to the immediate right of P. 

⇒ M sits on position 5, Q on 4 and P on 3.

2. O is on the other end.

⇒ O sit on position 1 and N occupies the last vacant seat.

Thus, Q sits third to the right of O.

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