Horatio drew a circle with a radius of 6x cm. Kelli drew a circle with a radius of 18y cm. What is the scale factor between these two circles? (this is a quiz question, you will recieve a medal for best answer)

A. x/3y

B. 2x/3y

C. 1/3

D. 2/3

I believe the answer Is A. x/3y.

The scale factor of these two circles is the ratio of their radii. This is shown below,

sf = r1 / r2 = 6x/18y

Simplifying the fraction by dividing both the numerator and the denominator by 6 gives an answer of x/3y. Thus, the answer is letter A.