Question

? ft Find the diameter of a circle with area of 112 ft2 Round your answer to the nearest tenth. ?

Answer 1

Data:

A=112 square feet

d=?

As the area of a circle is:

`A=\pi r^2`

Knowing the area you can find the radius, as follow:

`112=\pi r^2`

You use the formula of the area of a cicle to find the ratio, as you know the value of the area and the number pi.

You now the value of pi: 3.1416

Clear the r: you divide both sides of the equation by pi:

`(112)/(\pi)=(\pi r^2)/(\pi)`

As pi/pi is equal to 1 you get:

`(112)/(\pi)=r^2`
`r=\sqrt[]{(112)/(\pi)}`

Then the radius is:

`r=5.9708`

Knowing the radius you can find the diameter:

`d=2r`
`d=2(5.9708)`Then, the diameter is: 11.9ft
`d=11.9416\approx11.9`

Do you have any doubt?