Number Grids.

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Kathleen Smith 4449        Page         5/2/2007

Maths Coursework: Boots

Introduction:

For my coursework I will be investigating patterns in grids of different sizes. Within the grid each square has a number.

E.g.

For each boot (highlighted above) I will develop a formula to work out the total value of the numbers added up. The boot will consist of three numbers up and two across. My formula must show how to find out the added value of the boot if placed anywhere within the grid.

Grid 5x5

 

I found that in grid 5x5 that the formula for the added value of the boot is 4n+26. I discovered this by:

Working out the value of boots 1 to 4.

Boot 1= 1+6+11+12=30

Boot 2= 2+7+12+13=34

Boot 3= 3+8+13+14=38

Boot 4=4+9+14+15=42

Now I have this information I can begin to work on the sequence.

30   34   38   42

    4     4     4

                                  30-4=26  34-8=26 38-12=26 42-16=26

 These all-equal 26!

This shows that the formula is 4n+26=v

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n=smallest number in the boot.

v=total value of the boot.

To check my formula I will prove on another boot in the grid.

n = 9

4n = 4x9=36

36+26 = 62

9+14+19+20=62

To prove that 4n+26 is correct is to test it using n.

If I add these together n+n+5+n+10+n+11 it equals 4n+26.

This proves my formula for grid 5x5 is correct.

Grid 6x6

I found that in grid 6x6 that the formula for the added value of the boot is 4n+31. I discovered this by:

Working ...

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