Problem: If an arc of 60∘ on circle I has the same length as an arc of 45∘ on circle II, the ratio of the area of circle I to that of circle II is:
Answer Choices:
A. 16:9
B. 9:16
C. 4:3
D. 3:4
E. none of these
Solution:
36060​×2πr1​=36045​×2πr2​∴r2​r1​​=43​∴ Area (II) Area (I) ​=(43​)2=169​