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Expert Member
Chess board?
Let me ask you a very familiar question,
How many squares are there on a chessboard? How many rectangles?
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Contributing Member
Re: Chess board?
Number of squares in a chessboard:
1^2 + 2^2 + 3^2 + 4^2 + 5^2 + 6^2 + 7^2 + 8^2 = 204.
Formula N = (n(n+1)(2n+1))/6
Number of rectangles in a chessboard:
There are 9 vertical lines and 9 horizontal lines. To form a rectangle
you must choose 2 of the 9 vertical lines, and 2 of the 9 horizontal
lines. Each of these can be done in 9C2 ways = 36 ways. So the number
of rectangles is given by 36^2 = 1296.
Formula N = (n(n+1)/2)^2
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suresh
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Contributing Member
Re: Chess board?
Number of squares in a chessboard:
1^2 + 2^2 + 3^2 + 4^2 + 5^2 + 6^2 + 7^2 + 8^2 = 204.
Formula N = (n(n+1)(2n+1))/6
mmm suresh are u sure thats 204 squares in chess board!!!
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Contributing Member
Re: Chess board?
If you have a doubt then work it out manually (first work it out 3x3 and 4x4) and let me know if it is correct or not.
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suresh
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Contributing Member
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Junior Member
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Expert Member
Re: Chess board?
Right approach from Suresh. Hats off man
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Banned
Re: Chess board?
no yaar.........chess board has 205 squares....coz chess board itself is also a square
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