Stage: 2 Challenge Level: 
How are you checking that you have not got any of them twice?
How will you know you've got all the arrangements?
You may find it useful to record your arrangements on dotty paper.
How will you know you've got all the arrangements?
You may find it useful to record your arrangements on dotty paper.
Interactivities. Addition & subtraction. Combinations. Factors and multiples. Investigations. Equilateral triangles. Multiplication & division. Working systematically. Sets of shapes. Visualising.
Published October 2000.
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