Opp Corners


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A square box is placed on a number grid, covering four numbers. 

The numbers in the opposite corners are multiplied together and the difference between them is found. 

Try moving the grid around the box.  Multiply opposite corners again and find the difference between them.  What do you notice?

 

This number grid has 5 columns, try using different sized grids with different numbers of columns.  What do you notice?

Can you find any patterns or rules so that for any size grid you could calculate the difference in the opposite corners?

What happens if you try different boxes?           Try different sized squares and rectangles.
 

Key Stage 1:

Collect a number of counters between 1 and 20.  Can you lay them out in an array?

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An array of 6 can be done in two ways

                           

         
         
   

2 rows of 3

          

3 rows of 2

How many different arrays can be made with your number of counters?

Which number of counters have the most arrays? Why?