Question

What is the area of a circle with a circumference of 31.4Area-

Answer 1

The circumference of a circle is give by:

$C=2\pi r$

Plugging the value we have for the circunference we can find the radius:

$\begin{gathered} 31.4=2\pi r \\ r=\frac{31.4}{2\pi} \\ r=\frac{15.7}{\pi} \end{gathered}$

Now that we have the radius we remember that the area of a circle is:

$A=\pi r^2$

Plugging the value of r we have that:

$A=\pi(\frac{15.7}{\pi})^2=78.46$

Therefore the area of the circle is 78.46