Question

Circle has an area in square meters that is 5 times it’s circumference in meters. Can you calculate the circles radius? Explain your answer and find the radius if possible.

Can you calculate the circle’s radius if the circumference in meters was 6 times the area in square meters? Explain your answer and find the radius if possible.

Answer 1

Circle formulas for area and circumference are
A = π*r^2
C = 2π*r

Then the ratio (k) of area to circumference is
k = A/C = (π*r^2)/(2π*r) = r/2
Your questions want you to calculate the radius, so you can multiply this equation by 2 to get
r = 2k

(a) k = A/C = 5
r = 2*5 = 10 . . . . . meters

(b) k = A/C = 1/6
r = 2*(1/6) = 1/3 . . . . . meter