What's the radius of a circle who's circumference is 135.648

Circumference=diamter times pi

diamter=2 times radius

circumference=radius times 2 times pi

circunference=135.648

aprox pi to 3.14

subsitute

135.648=radius times 2 times 3.14

135.648=radius times 6.28

divide both sides by 6.28

21.6=radius

aswe ris radous=21.6 units

So, you know the circumference is 135.648, since you are trying to find the radius. We know C=π*d

135.648=3.14*d

135.648/3.14=d

thus, your diameter is 43.2

but remember, diameter is r^2

so 43.2/2

your radius is 21.6