MHB Inverse variation or direct or neither?

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The volume of a sphere, represented by the formula V=(4/3)pi*r^3, demonstrates a direct variation with the cube of the radius, r^3. While some may initially perceive it as direct variation with r, it is important to clarify that V does not vary directly with r itself. Instead, the relationship is defined by the constant factor (4/3)pi, indicating that volume increases with the cube of the radius. Therefore, the correct interpretation is that the volume varies directly with r^3, not r. Understanding this distinction is crucial in mathematical discussions of variation.
woof123
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the volume of a sphere: V=(4/3)pi*r3

To me it looks like it is direct variation with a power function (V/r3=(4/3)*pi)but i don't think that's what they're looking for
 
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Strictly speaking, neither, as $V$ does not vary directly with $r$.

It does, however, vary directly with $r^3$, as $\dfrac{4}{3}\pi$ is a constant.
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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