Start in triangle 1 and get to triangle 40 by choosing the correct series of options..
From 1 you can choose either 16 or 21..
(the triangles are all numbered in order from left to right, top to bottom)
if you chose 16 you may then choose 33 or 32
                          or
if you chose 21 you may then choose 32 or 12

best of luck.
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