So it's going to be 16 pi over 324 pi. And the pi's cancel out. And let's see, it looks like both of them are divisible by 4. If we divide the numerator by 4, we get 4. If we divide the denominator by 4, what do we get? 4 goes into 320, 80 times, it goes into 4 once, so we get an 81. So the probability, so I didn't even draw this to scale, this area is actually much smaller when you do it to scale.