The radius of the two circular fields is in the ratio 3: 5 the area of the first field is what percent less than the area of the second?
50%
60%
40%
64%
Explanation:
r = 3 $\pi r^2$ = 9
r = 5 $\pi r^2$ = 25
25 $\pi$ - 16 $\pi$
100 ---- ? => 64%