A Belt Around Two Pulleys
Source: Reader David Quinn, though I wouldn't be surprised to hear of
Given two pulleys of radius (X) and (Y), and the distance (D) between
their centers, find the circumference (Z) of the belt which goes around
both pulleys. Assume the belt touches at least part of each pulley, and
the pulleys can overlap (D can be less than X+Y).
With the definitions as above, if you're given X, Y, and Z, find D.
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