A round barn with 75 m circumference is surrounded by a fence that is 10 m from the barn all around. How long is the fence?I don't understand how...

We will use the circumference formula to find the original
radius.

We know that:

C =
2*r*pi where r is the radius.

Given that the circumference
is 75 m.

==> 75 =
2*r*pi

Now we will divide by
2pi.

==> r= 75/2pi = 11.94 m
(approx.)

Now we know that the distance between the circle
and the fence is 10 m.

Then the radius of the circular
fence is r+ 10 = 11.94+10 = 21.94 m.

Now we will calculate
the circumference of the fence given the radius
21.94.

==> C = 2*pi * r = 2*pi * 21.94 = 137.83
m

Then the length of the fence is 137.83
m