6 boys B1, B2, B3, B4, B5 and B6 are sitting around a rectangular table facing towards the centre (not necessarily in the same order). Two boys are sitting on each longer side and one boy is sitting on each shorter side of the table. B1 sits second to the left of B6. B4 sits second to the left of B5. B5 is the immediate neighbour of B6 and B2. B5 is not sitting opposite to B4. B1 is not sitting on a shorter side. Which pair of boys is sitting on a shorter side of the rectangular table?

B4 and B2

Given: There are 6 boys B1, B2, B3, B4, B5 and B6 are sitting around a rectangular table facing towards the centre (not necessarily in the same order).

So,

1) Two boys are sitting on each longer side and one boy is sitting on each shorter side of the table.

2) B1 is not sitting on a shorter side. B1 sits second to left of B6

3) B5 is the immediate neighbour of B6 and B2

3) B4 sits second to the left of B5. B5 is not sitting opposite to B4

Thus, the pairs of boys are B4 and B2, who are sitting on the shorter side of the rectangular table.