Question

The formula for finding the volume of a cone is V = 1/3πr2h. The volume of a cone is 300 cm3 and the height of the cone is 10 cm. What is the approximate radius of the cone?

A) 3 cm
B) 5 cm
C) 9 cm
D) 28 cm

Answer 1

if we solve for radius
V=1/3pir^2h
divide both sides by pih
V/(pih)=1/3r^2
times 3 both sides
3V/(pih)=r^2
sqrt both sides
sqrt(3v/(pih))=r

so if h=10
v=300
then
sqrt(3*300/(pi*10))=r
sqrt(900/10pi)=r
sqrt(90/pi)=r
use calculator
5.35=r
about 5
B is answer

Answer 2

the answer is b) 5



hope I helped!