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  • Problem
  • Student Solutions

 

A bag contains 12 marbles.

There are more red than green but taking the green and blue together exceeds the number of reds.

The total number of yellow and green marbles is more than the total number of red and blue.

Find exactly how many of each colour there are in the bag.

How many different solutions can you find?

 

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Plutarch's Boxes

According to Plutarch, the Greeks found all the rectangles with integer sides, whose areas are equal to their perimeters. Can you find them? What rectangular boxes, with integer sides, have their surface areas equal to their volumes?

All-variables Sudoku

The challenge is to find the values of the variables if you are to solve this Sudoku.

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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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