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Square Pegs

Age 11 to 14
Challenge Level Yellow starYellow starYellow star
Secondary curriculum
  • Problem
  • Student Solutions

Which is a better fit, a square peg in a round hole or a round peg in a square hole?
In other words, which peg fills a greater proportion of its hole?

A square peg in a round hole and a round peg in a square hole


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Do Unto Caesar

At the beginning of the night three poker players; Alan, Bernie and Craig had money in the ratios 7 : 6 : 5. At the end of the night the ratio was 6 : 5 : 4. One of them won $1 200. What were the assets of the players at the beginning of the evening?

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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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