## Annetta_Martin one year ago If the radius of a circle is multiplied by 2, then how many times larger is the circumference of the new circle? 2. 4. 8. pi.

1. kobesaurus

C = 2*pi*r , so if r is doubled the new C is 2*pi*2r , so it is 4pi.

2. kobesaurus

well 2 times larger.

3. kobesaurus

haha not quite, its just doubled. if r is double the circumference is doubled. so its just 2 times larger.

4. Annetta_Martin

I got it now, thanks! :)

5. kobesaurus

If it asks for area, the equation is $\pi*r^2$ so when its doubled the area quadruples. (4x times larger)