Question

The curved surface area of a cylinderical pillar is 264m sq and its volume is 924 m cube . Find the diameter and the height of the pillar

Answer 1

Given : CSA of cylinder = 264 m² and volume of cylinder = 924 m³
CSA of cylinder = 2πrh
264 = 2*22/7*r*h
r*h = (264*7)/44
r*h = 1848/44
r*h = 42 
h = 42/r ......(1)
Now, 
volume of cylinder = πr²h
Putting the value of h = 42/r in the below, we get
924 = 22/7*r²*42/r
924r = 924*7
r = 7 m
So, Radius is 7 m and the diameter will be 7*2 = 14 m.
And the height of the cylinder = 42/7 = 6 m

Answer 2

$\huge \underline \mathsf \red {SOLUTION:-}$

Given That:

• Curved surface area of cylinder = 264 m²
• Volume of cylinder = 924 m³

We know that,

• CSA of cylinder = 2πrh

So,

➠ 264 = 2 × 22/7 × r × h

➠ r × h = (264 × 7)/44

➠ r × h = 1848/44

➠ r × h = 42

➠ h = 42/r ……(1)

Now,

• volume of cylinder = πr²h

Substituting the value of h = 42/r in the volume equation, we get

➠ 924 = 22/7 × r² × 42/r

➠ 924r = 924 × 7

➠ r = 7 m

So,

Radius is 7 m and the diameter will be

= 7 × 2

= 14 m.

And the height of the cylinder

= h = 42/r

= 42/7

= 6 m

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