To find the volume of a beach ball with a radius of $9 \, \text{in.}$, we can use the formula for the volume of a sphere:

$V = \frac{4}{3} \pi r^3$

Step 1: Plug in the radius

$V = \frac{4}{3} \pi (9)^3$

Step 2: Compute $9^3$

$9^3 = 729$

$V = \frac{4}{3} \pi (729)$

Step 3: Multiply $729 \times \frac{4}{3}$

$\frac{4}{3} \times 729 = 972$

Thus, the volume is: $V = 972 \pi \, \text{in}^3$

Final Answer:

The volume of the beach ball is 972$\pi$ cubic inches.

Would you like additional explanation or related calculations?

Related Questions:

1. How do you derive the formula for the volume of a sphere?
2. What is the volume of a beach ball if the radius were doubled?
3. How does the volume change when the radius increases by 1 inch?
4. What would the surface area of this beach ball be?
5. How does the volume formula for a sphere compare to that of a cylinder?

Tip:

Always remember to cube the radius before multiplying by $\frac{4}{3}\pi$!