In a row of people standing in a waiting area, facing North, Hari stands seventh from the left end of the row and there are three people between him and the person standing at the exact centre of the row. How many people are standing in the row?

7 boys P, Q, R, S, T, U and W are sitting in a row facing north (not necessarily in the same order). No one is to the right of Q. R is fourth to the left of Q. W is second to the left of R. T is fourth to the right of U. P is not second to the right of U. Who is sitting to the immediate right of P?

5 boys R, M, N, B and C are sitting in a row facing north (not necessarily in the same order). Only B and R are to the left of M. N is to the immediate right of M. R is not at the ends of the row. Who is sitting to the right of N?

P, Q, R, S, T, U and V are sitting in a straight line, facing north. S is sitting second to the left of R. U is sitting fourth to the right of S. Only one person is sitting between P and V. Q is sitting second to the right of V. Only one person is sitting between Q and T. How many people are sitting between S and T?

Six people, A, B, C, D, E and F, are sitting in a row, facing north. F sits to the immediate left of A. C sits third to the left of D. C is an immediate neighbour of A. B sits to the immediate left of E. How many people sit between E and C?

Seven friends, D, E, F, U, V, W and X, are sitting in a straight line, facing north. No one sits to the right of D. Only three people sit between D and F. Only two people sit between F and E. X sits third to the left of V. W sits to the immediate right of V. How many people sit between U and E?

​In the following number sequence, find out how many times ‘7, 5 and 3’ have appeared together in the same order?
7 3 7 5 3 7 5 7 5 3 7 5 7 5 3 7 5 3

P, Q, R, S, T, U, V and W are sitting in a line facing North, not necessarily in the same order. ‘W’ is on the immediate right of ‘S’. ‘Q’ is on the immediate left of ‘T’. There are three persons between ‘Q’ and ‘W’. ‘P’ is adjacent to ‘U’. ‘V’ is second to the left of ‘W’. ‘P’ and ‘Q’ are not at the ends. ‘R’ is on the immediate right of ‘U’. Who is at the left end of the line?

Seven friends A, B, C, D, E, F and G are sitting in a row facing South. ‘B’ and ‘F’ are not sitting together. ‘C’ is sitting second to the left of ‘D’. ‘A’ is not sitting with ‘C’. ‘D’ is sitting fourth to the right of ‘E’. ‘A’ and ‘B’ are not sitting together. Only ‘E’ is sitting between ‘F’ and ‘G’. ‘G’ is sitting second to the left of one who is sitting second to the left of ‘A’. Name two persons who are sitting at the extreme ends?

Eight persons named A, B, C, D, E, F, G and H are sitting in a straight line facing the north direction. C is third to the left of D. B is second to the left of C. E is to the immediate left of A. D is second to the left of F. G is to the immediate right of D.
Who is immediate right of H?

A, B, C, D, E, F and G are standing in a row facing towards East. 'E' is at an extreme end and has 'G' as his neighbour. 'B' is to the left of 'D' and 'F' is to the right of 'D'. 'D' is at the fourth position from the South end. There is only one person between 'D' and 'A'. 'C' is to the right of 'A'. Who is standing to the immediate right of G?