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Age 14 to 16
Challenge Level Yellow starYellow star
Secondary curriculum
  • Problem
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Pick one of the cross-sections - perhaps the rectangle.

In this challenge, why does it help to think about the cross-section (profile) and not at all about how long the gutter might be?

The material "length" of the profile of the rectangle wasn't specified in the problem - perhaps it doesn't matter or perhaps we need to give it a value and see what happens.

By the end you will have used the idea that this problem is about shape and not about size.

What did your answers tell you about the "best shape" for the profile?

The picture suggests two other shapes to work with, but there are other possibilities, which did you think to try? Did you include a trapezium?

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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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