## anonymous 4 years ago The radius of one sphere is twice as great as the radius of another sphere. Find the ratio of their surface areas.

1. ParthKohli

Why don't you take a radius of 1 and a radius of 2 and then compare their surface areas? :)

2. ParthKohli

$$\color{Black}{\Rightarrow Area(Sphere ) = 4\pi r^2 }$$

3. anonymous

I tried that. I got 1:4.

4. ParthKohli

$$\color{Black}{\Rightarrow \textbf{Radius of 1}: 4\pi r ^2 \Longrightarrow 4\pi }$$ $$\color{Black}{\Rightarrow \textbf{Radius of 2}:4\pi r^2 \Longrightarrow 16\pi }$$ 1:4 is correct~!

5. anonymous

Thanks!! :) :) :)