How many persons sit between P and U?

T sits third to the right of S. T sits second to the left of U. We have two cases, first, when S sits at extreme left end and second, when S sits second from one of the extreme ends. Case 1: When S sits at extreme left end. S ____  _____  T _____ U ____ Case 2: When S sits at second from the left end. _____ S ____  _____  T _____ U Four persons sit between V and Q. V doesn't sit at any of the ends of the row. In case 1, Q sits at extreme right end. In case 2, Q sits at extreme left end. Case 1: When S sits at extreme left end. S         V         ____ T     _____        U         Q Case 2: When S sits second from the left end. Q         S         _____  _____  T    V    U P doesn't sit adjacent to R. Case 2 gets eliminated. The final arrangement is as follows. S         V         P/R     T          R/P     U         Q Either two or no one sits between P and U.