# Glass Half Full?

Geometry Level 5

Consider a glass in the shape of an inverted truncated right cone (i.e. frustrum). The radius of the base is 4, the radius of the top is 9, and the height is 7. There is enough water in the glass such that when it is tilted the water reaches from the tip of the base to the edge of the top. The proportion of the water in the cup as a ratio of the cup's volume can be expressed as the fraction $$\frac{m}{n}$$, for relatively prime integers $$m$$ and $$n$$. Compute $$m+n$$.

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