Question

Wha Is the approximate area of a circle with a diameter of 18 in?

Answer 1

Area of a circle:
`\pi`r²

We need to find the radius of the circle before we can find the area. The radius of a circle is half of the diameter. We are already given the diameter, so the radius would be 1/2d, where d = diameter.

Plug in 18 for d ⇒ 1/2(18) = 9.
The radius of this circle is 9 inches. Now we can plug in 9 for r in the formula for area of a circle.

`\pi`9² = 254.5 (rounded to tenths place)

The area of the circle is 254.5 in².

Answer 2

The area will be about 254.469 in^2