A board game uses tiles, each made up of 6 squares in a 3 x 2 arrangement. On each tile half of
the squares are coloured black, and half white; an example is shown below.
The tiles can be rotated but not flipped over (they are plain on the back). No two tiles are the
same.
What is the maximum number of different tiles there could be?
A 6
B 10
C 15
D 20
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