The meaning of the area is the measurement of a surface in this case a circle, which can be find by using the formula [tex]A= \pi r^{2} [/tex], where r is equal to the radius of the circle.
In this exercise is given that the diameter of a standard cardboard is 18 inches or a radius of 9 inches and it is asked to find its area. Therefore, to find the area of the circle you should substitute the value of the radius into the previous mention formula.
[tex]A= \pi r^{2}[/tex]
[tex]A= \pi (9 in)^{2} [/tex]
[tex]A= \pi (81 in^{2})[/tex]
[tex]A=254.47 in^{2} [/tex]
The area of the standard dartboard is 254.47 square inches or 254 square inches.
