Question

One circle has a diameter of 6 inches. A second, larger circle has a diameter that is four times the diameter of the first circle. What is the ratio of the area of the smaller circle to the larger circle? A 2:3 C 1:16 B 1:6.4 D 1:64

Answer 1

A=pi * r^2

6/2=3. 3^2=9. 9*pi=28.27

6*4=24. 24/2=12. 12^2=144. 144* pi=452.39

452.39/28.27=16

Ratio is 1:16 —— C

Answer 2

Let's find the answers.
Small Circle
The radius is half of the diamter. 3 inches.
π×r²=A
We'll use 3.14 for pi.
3.14×9
28.26 in²
Bigger Circle
6×4= 24
So the diameter is 24. The radius is 12.
3.14×12²
3.14×144
452.16 in²
Let's divide.
452.16÷ 28.26
16.
So C. 1:16.