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Rectangle Tangle

Age 7 to 11
Challenge Level Yellow star
Primary curriculum
  • Problem
  • Student Solutions
  • Teachers' Resources

Rectangle Tangle

 


 

The large rectangle above is divided into a series of smaller quadrilaterals and triangles. Each of the shapes is a fractional part of the large rectangle.

Can you untangle what fractional part is represented by each of the ten numbered shapes?

Why do this problem?

This activity gives the pupils opportunities to use and develop their visualising skills in conjunction with the knowledge of fractions. It's quite a contrast to just dealing with fractions numerically.

 

Possible approach

 

The pupils will most likely need to have had some previous experience of the shapes involved. Print out copies of this sheet to give to learners so that they have the image in front of them and can add marks to it, should they wish.
 

 

Key questions

 

What shapes have you found?
How big is this shape?
Which is the biggest/smallest shape?
Tell me how you found this out?

 

Possible support

The should probably be plenty of resources available for many children while with others you would want them to ask for particular resources to help them. Placing resources in front of same pupils seems to tell them that they should be using them, when you really want them to use their own ideas and make their own choices.  Some children may find it helpful to see the image on squared paper:

 

Possible extension

 

Encourage the pupils who have well with the challenge to create their own problems for others to solve.

 

 

 

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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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