Question

3. A rectangular paper of width 28 cm is rolled along its width and a cylinder of radius 40 cm is

formed. Find the volume of the cylinder.​

Answer 1

Given -

Width of a rectangular paper = 28cm

Now the rectangular paper is rolled along with its width to form a cylinder of radius = 30cm

Solution -

According to Question the rectangular paper is rolled from its Width therefore

Height of Cylinder = 28cm

Now We know that

$\boxed{\mathbf{Volume\: of \:Cylinder \:= πr^2 × h}}$

Where ,

H = Height = 28cm

H = Height = 28cm R = Radius = 30cm

Now Putting Values in the above formula we have

$\mathbf{Volume = \pi \: {30cm}^{2} \times 28cm}$

$\mathbf{= \pi \: 900{cm}^{2} \times 28 cm }$

Now Putting value of ' π ' = 22 / 7 Approx

We have ,

$\mathbf{Volume = \dfrac{22}{7}\: 900{cm}^{2} \times 28cm}$

Cancelling denominator 7 with numerator 28cm

we have ,

$\mathbf{Volume = \dfrac{22}{\cancel{7}} \times \cancel{28cm} \times 900\:cm^2}$

$\mathbf{ = 22 \: 4cm \times 900{cm}^{2} }$

$\mathbf{ = 88cm \times 900{cm}^{2} }$

$\therefore \sf{We \: have}$

$\boxed{\mathbf{Volume = 79,200{cm}^3}}$

Hence Required Answer =>

$\boxed{\mathbf{79,200{cm}^{3}}}$

HOPE THIS HELPS ❤️☺️

BE BRAINLY ⚡☃️

Answer 2

${\tt{\red{\underline{\underline{\huge{✿ Solution✿</p><p>}}}}}}$

A rectangular paper of width 28 cm is rolled along its width to form a cylinder.

Height of cylinder = h = 28 cm = width of rectangular paper.

And,

Radius of cylinder = r = 40 cm.

So, Volume of the cylinder = πr²h

=22/7×40×40×28

=140800cm³

∴ Volume of the cylinder = 140800cm³. (Answer).

Explanation:

$\huge \fbox \</strong><strong>p</strong><strong>i</strong><strong>n</strong><strong>k</strong><strong> {Hope \: it \: helps \: you}$