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## 'Cushion Ball Interactivity' printed from http://nrich.maths.org/

This interactivity is designed for the problem Cushion
Ball.

The interactive diagram below has two labelled points, A and B.
What is the shortest path from A to B if you bounce off one
cushion? In the diagram, you can click on the "Show" buttons to
draw the four possible paths from A to B. Which is the shortest?
You may move A and B around by clicking on them.

What is the shortest path from A to B using exactly two
cushions? The interactive diagram below shows the eight possible
paths from A to B. How would you calculate the shortest path?