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Through the Window

Age 7 to 11
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Primary curriculum
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We had these submissions from Colwich Primary School:

Ben and Will 

There are six windows shown and you could put them in pairs of windows which have the same perimeter but different areas, or the same areas but different perimeters. 

We chose to work with the £150 and £140 windows which have the same perimeter, but different areas. 

For the £150 window, A = 9 and P = 12.  For the £140 window, A = 8 and P = 12. 
This showed us that 1 square of A = £10. 

For the £140 window, this means that A = £80 and P = £60, which means that 1P = £5. 

So the answer is that a piece of glass costs £10 for every square of area, plus £5 for every square edge.

We checked our answers on all the other pieces of glass, and it worked every time.


Thank you very much for these submissions.

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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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