Sheep Pens
From Mycoted
A Farmer has twelve sheep and decides to put each of them into a separate pen; but to make the pens he has only 12 long hurdles and 6 half length hurdles. How can he do it?
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The farmer needs to arrange the 12 long hurdles in the shape of a hexagon made of 6 triangles, and then use the six short hurdles to divide each triangle into two.  Alan Butler spotted a solution which left a spare hurdle - can anyone improve on this?  Tim Bray spotted a solution which had 4 spare hurdles, although I suspect he might have cut the hurdles!!!!  Following my comments suggesting he may have cut some of the hurdles, Tim has come up with a couple of other solutions, which certainly don't need a saw. This one uses 11 long and 6 short, leaving one spare long hurdle  This one uses 12 long and 4 short, leaving two spare hurdles.  | |