SOLUTION: The stiffness of a rectangular beam is proportional to the breadth and the cube of the depth. Find the breadth of the stiffness beam that can be cut from a log of radius 10 inches.
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Question 1122182:  The stiffness of a rectangular beam is proportional to the breadth and the cube of the depth. Find the breadth of the stiffness beam that can be cut from a log of radius 10 inches. 
Answer by Boreal(15235)   (Show Source): You can put this solution on YOUR website!
 Draw this out, and the wood is a square with 20 inches diameter with side 20 sqrt (2)/2 for a square.  The total breadth/depth is 10 sqrt(2), the side of the square.
14.14 inches 
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