Question

Find the area of base and radius of a cylinder,

if its curved surface area is 1848 sq.cm and height is

21 cm​

Answer 1

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FIRSTLY FIND THE RADIUS :-

$ғᴏʀᴍᴜʟᴀ \: ᴏғ \: ʀᴀᴅɪᴜs = r = \sqrt{ \frac{v}{\pi \: h} }$

$sᴏ \: ᴛʜᴇ \: ʀᴀᴅɪᴜs = 5.29$

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----------ᴀɴsᴡᴇʀᴇᴅ-----------

Answer 2

Step-by-step explanation:

Given :-

Curved surface area is 1848 sq.cm and height of a cylinder is 21 cm

To find :-

Find the area of base and radius of a cylinder?

Given that

Height of a cylinder = (h) = 21 cm

Let the radius of the base be r cm

We know that

Curved Surface Area of a cylinder = 2πrh sq.units

On Substituting the value of h in the above formula then

CSA of the given cylinder = 2πr×15 cm²

=> CSA = 30πr cm²

According to the given problem

Curved Surface Area of the given cylinder

= 1848 cm²

=> 30πr = 1848

=> 30×(22/7)×r = 1848

=> (30×22)×r/7 = 1848

=> 660r/7 = 1848

=> 660r = 1848×7

=> 660 r = 12936

=> r = 12936/660

=> r = 196/10

=> r = 19.6 cm

Radius of the cylinder = 19.6 cm

The base of the cylinder is a circle

Area of the base of the cylinder = Area of a circle

=πr² sq.units

=> (22/7)×(19.6)² cm²

=> (22/7)×19.6×19.6

=> (22×19.6×19.6)/7

=> 22×19.6×2.8

=> 1207.36 cm²

Area of the base of the cylinder = 1207.36 cm²

Answer:-

Area of the base of the given cylinder =

1207.36 cm²

Radius of the given cylinder = 19.6 cm

Used formulae:-

• Curved Surface Area of a cylinder = 2πrh sq.units

• Area of the base of the cylinder =πr² sq.units

• π = 22/7

• r = radius of the cylinder