Answer:
IF TWO VALUES ARE PROPORTIONAL THEY CAN BE CONNECTED IN TERMS OF k BY MAKING THEM IN A STUCTURE OF AN EQAUTION LIKE GIVEN BELOW. HERE AS THE PROPORTIONAL VALUES ARE RADIUS AND CIRCUMFERENCE WE USE THE GIVEN VALUES AND CREATE EQAUTION LIKE BELOW
r=kC
⇒WE CAN TRASNPOSE THIS TO GET
kC/r=0
⇒C/r=1/k
RECIPROCATE IT TO GET
⇒r/C=k
Maybe this will be correct answer
