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Platinum Enthusiast
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I'm just as confused as frankvan about the given problem. If this is about the possible shapes of a convex (or concave?) polyhedron with 8 faces, then more info is needed.
On the other hand, if this is about a box with pictures on 8 sides, ignoring the top and bottom, then it is equivalent to asking how many distinct ways 8 guests may be seated at a round dinner table, not counting rotations of the table. The answer is 7! (7-factorial) = 7*6*...*2*1 = 5,040.
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Diamond Enthusiast

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Are the sides otherwise distinguishable? I would guess they are not, in which case the answer would be less than 8-factorial (how much less, I'm not sure).
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Diamond Enthusiast

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Tried to edit, but I apparently timed out. A more complete reply with a partial thinking through:
Are the sides otherwise distinguishable?
If they are, Pin~Jinx is correct.
I would guess, however, they they are not. In that case, you would need a correction factor to account for arrangements that are only rotations of other arrangements. For a round table with 8 seats, the correction would be to divide by the number of seats. That is 8!/8 = 7!, which is the answer Professor gave. However, I'm not sure that 8 is the appropriate factor for an 8-sided object. For the 8-sided object, you can rotate to 4 positions horizontally and to 4 positions vertically. I think those need to be multiplied rather than added (that is, I think there are 4 vertical rotations for each of the 4 horizontal rotations). That would give 8!/(4*4) = 2520.
I may be completely off about that, and I don't think I'm being particularly clear, but I thought I should put in my two cents, and I don't have time for three at the moment. Maybe Prof. and Pin~jinx can sort out if what I'm saying is correct and can better explain it.
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Platinum Enthusiast
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methos, are you picturing this box as an octahedron? My image is of an octagonal prism, the end faces (top and bottom) of which are ignored. Another possibility is a hexagonal prism with the end faces counting, in which case there are (8*7/2!)*(5!)*2 = 6,720 permutations.
The fact is, we need the original questioner to explain what was meant by "a box that has 8 sides."
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Diamond Enthusiast

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Yes, I was picturing an octahedron (I missed your comment about ignoring the top and bottom)... something like: You're right that we need more info. Even if it's an octagonal prism, now that I think about it, it matters whether or not the top and bottom are interchangeable. If not, I'd agree with 8!. If so, I think it would be 8!/2.
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