Question

Question in the picture

Answer 1

The formula for the area of a circle is
\[\large Area=\pi r^{2}\]
The area of circle B is
\[\large A _{b}=\pi \times15^{2}\ cm^{2}\]
The area of circle A is
\[\large A _{a}=\pi \times5^{2}\ cm^{2}\]
The ratio of area of circle B to the area of circle A is therefore given by
\[\large \frac{A _{b}}{A _{a}}=you\ can\ calculate\]