Question 1028947
Circumference
{{{C = 2*pi*r}}}


Area
{{{A = pi*r^2}}}


Ratio of circumference to area
{{{C/A = (2*pi*r)/(pi*r^2) = (2)/(r)}}}


Now plug in the radius of 4 (diameter = 8, the radius is half of this)


{{{(2)/(r)=(2)/(4)=1/2}}}


Final answer: {{{1/2}}} (in decimal form, this is equal to 0.5)