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Attach weights of 1, 2, 4, and 8 units to the four attachment
points on the bar. The bar strangely has no weight of its
Move the bar from side to side until you find a balance point. Is
it possible to predict that position
(you might find it helps to look at the problem called "Inside
Which arrangements produce balance points outside the central
interval (between the two inner attachment points for
If the bar now does have weight, what is the least weight it could
have with no arrangements that produce balance points outside the
You only need the 1, 2, 4 and 8 unit weights for the problem set
but the others are there to let you explore, conjecture and test -