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Cushion Ball

Age 16 to 18
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Why do this problem?
The context is interesting and this can be an exercise in finding distances using coordinates. This process, of repeatedly reflecting the snooker table in its sides, occurs in many areas of advanced mathematics and for a simple introduction see the article In Space Do All Roads Lead Home?

Possible approach
Use the hint.

Key question
We know the ball bounces of the cushion at an equal angle so how do we use this fact to find the right point on the cushion to aim for?

Possible support
See Snookered.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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