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Arrangements

Stage: 2 Challenge Level: Challenge Level:1

Arrangements


In a 3 by 3 grid, it is possible to place some counters on the grid so that there is an even number of counters in every row and every column. (We are taking zero as an even number.)
For which numbers of counters is this possible?
You may like to use this interactivity to explore your ideas.
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Engaging with this problem will help children explain patterns they find linked with important properties of numbers.