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geometry senior
Problem
Two right circular cones with vertices facing down as shown in the figure below contain the same amount of liquid. The radii of the tops of the liquid surfaces are cm and cm. Into each cone is dropped a spherical marble of radius cm, which sinks to the bottom and is completely submerged without spilling any liquid. What is the ratio of the rise of the liquid level in the narrow cone to the rise of the liquid level in the wide cone? 
(A)
(B)
(C)
(D)
(E)
Solution
Final Scenario For the narrow cone and the wide cone, let their base radii be and (for some ), respectively. By the similar triangles discussed above, their heights must be and respectively. We have the following table: Recall that Equating the volumes gives which simplifies to or Finally, the requested ratio is Remarks 1. This solution uses the following property of fractions: For unequal positive numbers and if then 2. This solution shows that, regardless of the shape or the volume of the solid dropped into each cone, the requested ratio stays the same as long as the solid sinks to the bottom and is completely submerged without spilling any liquid.
Final answer
E