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Countdown

Age 7 to 14
Challenge Level Yellow star
Secondary curriculum
  • Game
  • Getting Started
  • Teachers' Resources

Countdown printable sheet
Countdown printable sheet - cards


Here is a chance to play a version of the classic Countdown Game.

The challenge is to use the numbers available and the four standard operations (addition, subtraction, multiplication and division) to hit the target.

Start by choosing any six cards. The top row always contains the numbers 25, 50, 75 and 100, and the bottom row contains the numbers 1 to 10. Alternatively you could click on "Quickstart". Then click on "Generate new target" and the computer will choose a target.

You can only use each card once in your solution, and it is always possible to find a solution.

You may like to explore different levels of the game using the Settings menu (the purple cog).





Once you've had a go, click on "Show solutions" to show some possible ways in which the target can be reached.

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Squaring the Circle

Bluey-green, white and transparent squares with a few odd bits of shapes around the perimeter. But, how many squares are there of each type in the complete circle? Study the picture and make an estimate.

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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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