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A Ball of Cable is a Ball of Fun

IBM is currently running an interesting advertisement campaign called "out with cables," developing a need for their new "blade" structure. The key ingredient in this campaign is a huge sphere supposedly made by rolling up computer cables into a huge ball. The current IBM video captures both the idea and the huge size of the ball of cables.

Problem: Estimate the volume of the ball cables, then estimate the number of linear feet of cables needed to create the ball.


Hint: Use other objects in the picture as benchmarks to help you estimate a diameter or radius.


Solution Commentary: The determination of the volume should be quite straightforward...but the length of the cables?

One good approach is to get some string or several long electrical cords. After you measure their lengths, wrap them into a ball and determine their volumes. Try to develop a proportial relationships between length of cord and column of ball of that same cord.