00:01
Let's say i have a roll of paper towel, and i want to know actually how much paper towel is on my roll.
00:11
So i could get the volume of that whole cylinder, which i have the formula for that right here.
00:17
This is the formula for the volume of the cylinder.
00:19
But my roll of paper towel has that cardboard tube down the center of it.
00:23
So i need to figure out the volume of the whole roll of paper towel, including the cardboard tube.
00:30
And then i need to figure out the volume of the cardboard tube and subtract that from my hole.
00:35
So i'm going to be looking for some volumes, some cylinders.
00:39
So the first thing i want to do is find the volume for the whole thing.
00:45
So the volume for my whole is going to be, my volume is pi.
00:54
And since the diameter of the whole roll is 8, my radius is going to be 4.
01:00
And 4 squared is 16...