Question

The curved surface area of a cylinder is 154 cm2
. The total surface area of the cylinder
is three times its curved surface area. Find the
(i) radius of the cylinder
(ii)height of the cylinder.

Answer 1

Answer:

Given Curved surface area of cylinder = 154 cm2 And

We know Curved surface area of cylinder =2 π r h

Here r = Radius of base of cylinder and h = Height of cylinder

So,

2 π r h = 154 ----- ( 1 )

And

Also given : The total surface area of the cylinder is three times its curved surface area .

And

We know Total surface area of cylinder = 2 π r h + 2 π r 2

So,

2 π r h + 2 π r 2 = 3 ( 154 )

Substitute value from equation 1 , we get

⇒154 + 2 π r 2 = 462

⇒2 π r 2 = 308

⇒π r 2 = 154

⇒227×r2 = 154 ⇒17×r2 = 7⇒r2 = 72⇒r = 7

Substitute that value in equation 1 , we get

2 ×π × 7 × h = 154 ⇒π h = 11 ⇒227× h = 11 ⇒ h = 7722 ⇒ h =3.5

So,

Radius of our cylinder = 7 cm and Height = 3.5cm

We know Volume of cylinder = π r2 h

So,

Volume of our cylinder = 227×7 × 7× 3.5 = 22 × 7 × 3.5 = 539 cm3 ( Ans )

Step-by-step explanation:

hope its help u

Answer 2

answer is in the attachment.

I hope it helps you.