The ratio of the radius of two circles is 2: 3, and then the ratio of their areas is?	Choose the correct answer
A) 1:7 B) 2:9 C) 4:9 D) 3:7 E) 3:4
r1: r2 = 2: 3   Î r1^2: Î r2^2   r1^2: r2^2 = 4:9   Answer: 4:9
<result>C</result>
The ratio of the radius of two circles is 2: 3, and then the ratio of their areas is?