The answer is 5.9059 .... heard of a calculator?
Data points
a data series
an x axis
a y axis
a legend
hope this helps (:
The easy way is to count outcomes. Of the 36 equally probable outcomes, 10 are less than or equal to 5, so the probability is 10/36 = 5/18.
Since the circumference is 80, you know that the equation used was:

Divide by pi and you'd get d = 25.465
Divide that by 2 to get your radius.
25.465 / 2 = 12.723 = r
The area formula for a circle is

So,

= 508.544 square feet