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Are You Kidding

Age 14 to 16
Challenge Level Yellow starYellow star
  • Problem
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You can calculate the length of the two remaining sides and then use Pythagoras' Theorem.

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Building Tetrahedra

Can you make a tetrahedron whose faces all have the same perimeter?

Rudolff's Problem

A group of 20 people pay a total of £20 to see an exhibition. The admission price is £3 for men, £2 for women and 50p for children. How many men, women and children are there in the group?

Our Ages

I am exactly n times my daughter's age. In m years I shall be ... How old am I?

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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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