Question

if the diameter of a circular cylinder is 28 cm and its height is 20 CM then the curved surface area is?​

Answer 1

Given :

• Diameter of Cylinder is 28cm.
• Height of Cylinder is 20cm.

To Find :

• Curved Surface Area of Cylinder.

Solution :

$\longmapsto\tt{Radius=\cancel\dfrac{28}{2}=14cm}$

$\longmapsto\tt{Height=20cm}$

Using Formula :

$\longmapsto\tt\boxed{C.S.A\:of\:Cylinder=2\pi{rh}}$

Putting Values :

$\longmapsto\tt{2\times\dfrac{22}{{\cancel{7}}}\times{{\cancel{14}}}\times{20}}$

$\longmapsto\tt{2\times{22}\times{2}\times{20}}$

$\longmapsto\tt\bf{7040{cm}^{2}}$

So , The Curved Surface Area of Cylinder is 7040cm²..

_______________________

• C.S.A of Cylinder = 2πrh
• T.S.A of Cylinder = 2πr(r+h)
• Volume of Cylinder = πr²h

_______________________

Answer 2

Answer:

The Above Answer is wrong❌

Correct answer : 1760

If we will multiply

2×22×2×20

Then the answer will be 1760 and not 7040.

Suggestion: If you don't known the answer don't give .