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Cut the chess board

Cut the chess board

Posers and Puzzles

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Can you cut a chess board into four rectangles so they have the ratios 1:1, 1:2, 1:3 and 1:4 respectively?
You cannot cut squares in parts.

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I think you cannot do that. Maybe my calculations are wrong:
I suggest letting x be the largest part of the board. Then we can rite the following equasion:
x + 1/2x + 1/3x + 1/4x = 64
Multiply the equasion by 12:
12x + 6x + 4x + 3x = 768
x = 30.72

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Originally posted by FabianFnas
Can you cut a chess board into four rectangles so they have the ratios 1:1, 1:2, 1:3 and 1:4 respectively?
You cannot cut squares in parts.
Lets see...

To cut the board into 4 rectangles, we must make 3 paralle cuts or 2 perpendicular cuts.

The first option is impossible since the 1:1 rectangle is a square.

The second option is impossible since the rectangle having no common edge with the 1:1 rectangle is a square, but 1:2, 1:3, 1:4 are not squares.

So there is no solution, even if cutting squares in parts is allowed.

1 edit
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Well, a square is a special kind of rectangle with the ratio 1:1. We do agree on this, don't we?

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Oh, I misunderstood the question. I thought you meant that the rectangles relate to each other as 1 to 1, 1 to 2 and so on by their square.

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Easier to say with a diagram, but split into the following blocks:

a1->d8 (2:1)
e1->f8 (4:1)
g1->h6 (3:1)
g7->h8 (1:1)

I got there by looking for +ve integer solutions to a^2 + 2b^2 + 3c^2 + 4d^2 = 64.

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I think I used a simlar method, the areas of the simpler ratios were 1,2,3 and 4. I then multiplied these by 4 to make a total of 64 (doubling the sizes). This was a slight hunch because 64=2^6 so I assumed trebling would not help.

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Totally correct! Well done.
(and nice graphics, deriver69 !)

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Can you cut the chessboard into four congruent shapes, each of which contains exactly one of the following squares: a1, b2, c3, d4?

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Originally posted by Jirakon
Can you cut the chessboard into four congruent shapes, each of which contains exactly one of the following squares: a1, b2, c3, d4?
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Originally posted by David113
Lets see...

To cut the board into 4 rectangles, we must make 3 paralle cuts or 2 perpendicular cuts.

The first option is impossible since the 1:1 rectangle is a square.

The second option is impossible since the rectangle having no common edge with the 1:1 rectangle is a square, but 1:2, 1:3, 1:4 are not squares.

So there is no solution, even if cutting squares in parts is allowed.
Shame:'(
I forgot the third way, which gives a solution🙁

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Originally posted by mtthw
[fen]pRRRRRRR/pRrrrrrr/pRrPPPPr/pRrPppPr/pRrrRpPr/pRRRRpPr/ppppppPr/PPPPPPPr[/fen]
I like mine better.. 😛

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Originally posted by mtthw
[fen]pRRRRRRR/pRrrrrrr/pRrPPPPr/pRrPppPr/pRrrRpPr/pRRRRpPr/ppppppPr/PPPPPPPr[/fen]
Great. A swastika.

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Originally posted by Guych
I think you cannot do that. Maybe my calculations are wrong:
I suggest letting x be the largest part of the board. Then we can rite the following equasion:
x + 1/2x + 1/3x + 1/4x = 64
Multiply the equasion by 12:
12x + 6x + 4x + 3x = 768
x = 30.72
You're calculating areas. The problem is about ratios.

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