00:01
In this form, we have the formula, v is equal to one -third pi r squared h, which you may recognize as the formula for the volume of a cone.
00:13
We are told that the height, h is equal to 12, and when the volume is 50, we want to find what r is equal to.
00:22
So we can solve for r.
00:24
We can do that by multiplying by 3 to get rid of the 1 -third, and then divide.
00:31
By pi h to get rid of our other constants here.
00:36
And so that would give us that r squared is equal to 3 v, divide by pi h.
00:54
And then to solve for r, you can just take the square root of both sides.
01:15
And then finally, we can just use the information we're given.
01:19
We told that h is 12 and v is 50.
01:23
So if we plug in v, we have 3 times 50, which is 100.
01:30
If we plug in h is equal to 12, that gives us 12 divide by pi...