Place 9 balls ("o") in the intersections of the grid below to achieve 10 straight lines, each line containing 3 and exactly 3 balls. You may assume, if you need, that each cell is a perfect square.
+---+---+---+---+---+---+---+---+
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+---+---+---+---+---+---+---+---+
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+---+---+---+---+---+---+---+---+
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+---+---+---+---+---+---+---+---+
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+---+---+---+---+---+---+---+---+
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+---+---+---+---+---+---+---+---+
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+---+---+---+---+---+---+---+---+
To pcb: I did in fact spend a fair amount of time trying to find a solution to your problem as written (as I interpreted it) before looking at the original post (by Leming). It seemed like an interesting challenge. Since your recent reply did not clarify your intention, perhaps it still is, though I got far enough to be fairly confident that there was no solution along those lines (though I didn't see a clear proof of that -- perhaps an interesting challenge in itself). I think I would be well advised to follow your prescription and just ignore puzzles which are not clearly stated. Your pique is not piquant.
pick a pint of pickled pique...
