Circumference of a circle =

They are all multiplied by each other
r = radius
we know our radius is 40
and...

= 3.14
so we would use this expression 3.14 x 40 x 2 As a added bonus ill solve it for you :P
3.14 x 40 x 2 = 251.2
The circumference of this ice skating rink is 251.2 feet
Explanation:
Unclear question. But I inferred this to be clear rendering of your question;
1) It is considered a circle and a certain point. The expressions dot inside the circle, dot on circle, or dot outside the text describe the position of a dot relative to a circle. In figure 2 are drawn: a circle C of center O, points on the circle, points outside the circle and points inside the circle. a) Name the points inside the circle; b) Name the points that belong to the circle; c) Name the points outside the circle.
2) Consider any point P and a circle C of center O and radius r. Compare the distance OP with the radius of the circle if: a) The point is inside the circle; b) The point is on the circle; c) The point is outside the circle.
85/100 is greater
85/100=.85 or 85%
21/25=.84 or 84%
.85 is greater than .84 so 85/100 > 21/25
Y=kx, k is not equal to 0
when y=32,x=3, 32=3k
k=32/3
so y=32/3*x
when y=15, 15=32/3*x
x=45/32