Stage: 3 and 4 Challenge Level: 
Take some time to look at the route followed by the arrows in this diagram.
Then look away and describe the path to a friend.
If the pattern of arrows continues forever, which point will the route visit immediately after (18,17)? Explain how you know.
How many points will be visited before the route reaches the point (9,4)?
Explain how you worked it out.
A poster of this problem is available here.
Manipulating algebraic expressions/formulae. Real world. Triangle numbers. Generalising. Visualising. smartphone. Mathematical reasoning & proof. Making and proving conjectures. Coordinates - first quadrant. Workshop.
Published March 2007,April 2007.
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