A jazz group plans to play six pieces - J, K, L, M, N and O - during a set . Each piece will be played exactly thrice. The order in which the pieces are to be played is subject to the following conditions:
N must be played before J and before O.
M must be played later than J.
K must be the third Piece.
Which of the following could be the order in which the pieces are played ?

Options

A. J is played after K.
B. M is played after N.
C. k is played first.
D. O is played sixth.

Explanation

Begin by summarising the information: `Nlt(J+O)`
`JltM`
K = 3
There is one further conclusion that can be drawn. Since N is to be played before J and J before M, N must be played before M.
As for (1).J cannot be played last because J is played before M. As for (2), K must be played third, not first. As for (3), M cannot be played second, because (as we learned above) both J and N must be played before M. As for (4), it is K that must be played third `lt197gt` not N. (5), however, is a possibility, as shown by the diagram:
`{:("1 2 3 4 5 6"),("N J K L M O"):}`