A beach ball is a sphere, so we will need to know how to find the volume of a sphere. V=4π(r³/3) We have the diameter, but not the radius. To find the radius, it is half of the diameter. 10÷2=5 Now let's plug it in. 4π(5³/3) Let's solve. 4π= 12.56 5³= 125 125÷3= 41.67 (repeating 6) 41.67×12.56= 523.3752 523.33 cubic inches is the volume of air contained inside the beach ball. The reason I picked that answer is because we rounded up to 41.67, when there was a repeating 6. So we should expect for the answer to be a couple decimals lower from the answer we got. Tell me if this helps!!