Describe an informal argument for the volume of a cone. If you know the volume of a cylinder, what must you do to find the volume of a cone that has the same height and base radius?(1 point)

Responses

You need to divide the volume of the cylinder by 13.
You need to divide the volume of the cylinder by Start Fraction 1 over 3 End Fraction .

You need to multiply the volume of the cylinder by 13.
You need to multiply the volume of the cylinder by Start Fraction 1 over 3 End Fraction .

You need to add 3 cubic units to the volume of the cylinder.
You need to add 3 cubic units to the volume of the cylinder.

You need to multiply the volume of the cylinder by 3.

1 answer

To derive the volume of a cone based on the volume of a cylinder, you can think of how the shapes relate to each other. A cone fits nicely into a cylinder that has the same base radius and height.

  1. Understanding the Shapes: Imagine a cylinder and a cone with the same height \( h \) and the same base radius \( r \). The cylinder completely encloses the cone.

  2. Visualizing the Volume: If you fill the cylinder with a liquid, the cone occupies part of that space. Through experimentation (like using physical models), one can discover that the volume of the cone is actually only a fraction of the volume of the cylinder.

  3. Finding the Relationship: It’s been established (through geometry) that the volume of the cone is exactly one-third of the volume of the cylinder when both share the same height and base. If the volume of the cylinder is given by \( V_{cylinder} = \pi r^2 h \), the volume of the cone can be derived as \( V_{cone} = \frac{1}{3} \pi r^2 h \).

Therefore, to find the volume of the cone, you need to multiply the volume of the cylinder by \( \frac{1}{3} \).

The correct response is: You need to multiply the volume of the cylinder by \( \frac{1}{3} \).