Question

Using π as 3 1/7, what is the area of the circle with a diameter of 8.4 cm​

Answer 1

if the diameter is 8.4, that means its radius must be half that, or 4.2

`\textit{area of a circle}\\\\ A=\pi r^2 ~~ \begin{cases} r=radius\\[-0.5em] \hrulefill\\ r=4.2\\ \pi =3(1)/(7)\\[1em] \qquad (22)/(7) \end{cases} \implies A=\cfrac{22}{7}(4.2)^2\implies A=55.44`