Question

The height of the right circular cylinder is 10.5cm. If three times the sum of the areas of its two circular faces is twice the area of the curved surface area. Find the radius of its base. (The answer must be 49.But how to solve?)

Answer 1

$here \: is \: the \: answer$

GIVEN::::::

HEIGHT OF CYLINDER = 10.5

TO FIND::::::

RADIUS OF THE CYLINDER

FORMULA USED:::::

$2\pi \: rh \: \: \: and \: \: \pi {r}^{2}$

HOW TO FIND::::::

Height of cylinder = 10.5 cm

Let radius of cylinder = r cm

So,

Area of two bases of cylinder = 2πr2

Area of curved surface of cylinder = 2πrh

Now,

=3(2πr2) =2( 2πrh)

= 6πr2 = 4πrh

= 3r = 2 x 10.5 cm

r=2x 10.5 /3 =7cm

Radius of base of cylinder = 7 cm

HOPE IT HELPS U.. ..❤