You are given two different circles. The diameter of the first circle is the radius of the second circle. What is the ratio of the area of the larger circle to the area of the smaller circle. Your answer should be in the form of a simplified fraction. I have no idea where to start. Please help.

Question

Thank you.

Answer 1

When comparing similar figures (eg. circles with circles, squares with squares, etc.)
Ratio of area
= (ratio of linear dimension)²

In this case,
ratio of diameters=2/1=2
Can you find the ratio of areas?