if two cylinder are similar and the ratio between the lengths of their edges are 2:5. What is the ratio of their volumes?

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anonymous · Answer

Well, volume of a cylinder is $$V= \pi r^2l$$ where l is the length of the cylinders edge.  The two cylinders are "similar" which I take to mean have a base of equal radii.  So the ratio of their volumes is then,$$V _{1}/V _{2}= \pi r^2l _{1}/\pi r^2l _{2}=l _{1}/l _{2}$$Thus the ratio of their volumes is the same as the ratio of their lengths (assuming the radii of the bases are the same).  $$V _{1}/V _{2}=l _{1}/l _{2}=2/5$$