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Squares on a Chessboard
You don't need to know anything about the game of chess for today's Mathematical Morsel.
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At first, it looks like the answer is 64. However, in this case, I want ALL the squares with edges along the lines of the chessboard. So there are not only single squares (of which there are 64) but also 2-by-2 sized squares, and 3-by-3 sized ones, all the way up to the 8-by-8 square board itself. So:
In mathematics, a useful way to tackle such a problem is to take a smaller case as an example. So, suppose on a distant planet, chess was played on a board which was 2-by-2.
Also, to help our investigations let's organize our search.
What sizes of square are possible on this small 2-by-2 board?
Single squares and 2-by-2 squares only!
Let's put this in a table and you can write in your answers:
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Have you spotted the pattern in the results? [Hint: we are counting SQUARES.]
Now can you tell me how many squares there are in total in the 8-by-8 chessboard if all the squares have sides along the rows or columns on the board?
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Reference
John Mason's Thinking Mathematically, published by Addison-Wesley, 1985, ISBN 0-201-10238-2 is a good book for further investigations of this type, but needs some familiarity with school-level algebra.
Patterns