Question

if the volume of cylinder is 686π cm3 and height of cylinder is twice it's radius.find it's radius​

Answer 1

Vol. of cylinder is 686pie
Pie rsquare h + 686 pie
rsquare h = 686
r cube= 343
r=7

Answer 2

The radius of cylinder is equal to 7 cm.

Step-by-step explanation:

Given,

The volume of cylinder =  686π $cm^3$

Let the radius of cylinder = x

∴ The height of cylinder = 2x

To find, the radius of cylinder = ?

We know that,

The volume of cylinder $=\pi r^2h$

∴ $\pi x^2(2x)$ = 686π

⇒ $2x^{3} =686$

⇒ $x^{3} =343$

⇒ $x^{2} =7^{3}$

⇒ x = 7 cm

∴ The radius of cylinder = 7 cm

Thus, the radius of cylinder is equal to 7 cm.