# Formula Volume of a Sphere

Sphere's Volume

### Example

The volume of the sphere pictured on the left is:

$$v = \frac{4}{3} \pi r^3 \\ v = \frac{4}{3} \pi \cdot 3^3 \\ v = 36 \pi \\ = 113.1 \\$$

### Practice Problems

##### Problem 1

$$v = \frac{4}{3} \pi r^3 \\ v = \frac{4}{3} \pi \cdot 7^3 \\ = 457.3 \text{ cubic inches} \\$$

##### Problem 2

First, remember that we need to divide the diameter by 2 to get the radius of 5 for our formula:

$$v = \frac{4}{3} \pi r^3 \\ v = \frac{4}{3} \pi \cdot 5^3 \\ v = 36 \pi \\ = 523.6 \text{ cubic inches} \\$$