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:

$\frac{112}{\pi}=\frac{\pi r^2}{\pi}$

As pi/pi is equal to 1 you get:

$\frac{112}{\pi}=r^2$$r=\sqrt[]{\frac{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?