00:01
All right.
00:02
So for this question, we want to calculate the uncertainty in the area of a circle whose radius can either be 14 .6 plus or minus 0 .5 centimeters.
00:17
So basically what we want to do here is calculate the area with the largest possible radius.
00:25
And then again, for the smallest possible radius.
00:27
And then we're going to get a range for our area.
00:30
And find that confidence interval for the area.
00:36
And so first, if we figure out what our largest radius would be, that would be 14 .6 .05, and we will get 15 .1 as our larger radius.
00:50
And then our smaller radius would be 14 .6 minus 0 .5.
00:55
And that would be 14 .1.
00:57
And so just remember that the area for a circle is pi r squared.
01:03
So that formula is going to be really important.
01:06
And then we'll just write out what our area would be if we plug in our larger radius, which is the 15 .1.
01:15
And then we'll write out the area for our circle if we plug in the smaller radius, which is 14 .1.
01:22
And so if we multiply this out, we would get 715 .95 centimeters...