00:01
Here we want to find the circumference of a circle with a radius of 6 .3.
00:07
Well, the circumference of a circle is going to be 2 pi r as we're given.
00:13
So we want to find the circumference, so that's just 2 pi times 6 .3.
00:20
Now we want to find it in both terms of pi and in decimal form.
00:24
So i'm just going to take 6 .3 times 2, which is 12 .6 .6.
00:33
And then i can multiply that by pi in my calculator and i get 39 .584.
00:44
So that is b.
00:48
Next we want to find the circumference of a circle with a diameter.
00:53
So number eight, we want to say the diameter is 120.
00:57
Well if the diameter is 120, that means the radius is half that, which is 60.
01:01
So this is essentially the same question...