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Age 7 to 11
Challenge Level Yellow star
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Sixteen children are standing in four rows of four, one behind the other. They are each holding a card with a number on it. In each column, all four children are wearing clothes of the same colour.

Red

Blue

Yellow

Green

 
Each child in blue is holding a number which is four more than the child next to them who is wearing red.

The children in yellow each have a number which is double the number of the child in the same row wearing red.

Some of the numbers that the children in red, blue and yellow are holding are missing. What should these numbers be?

How have the numbers of the children in green been worked out? What are the two missing numbers?

If there was another row of four children standing at the back, behind the fourth row, what numbers would they be holding?

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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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