Aptitude - Volume and Surface Area - Discussion
Discussion Forum : Volume and Surface Area - General Questions (Q.No. 11)
11.
The curved surface area of a cylindrical pillar is 264 m2 and its volume is 924 m3. Find the ratio of its diameter to its height.
Answer: Option
Explanation:
 r2h |
= | 924 |  r = |
 |
924 | x 2 |  |
= 7 m. |
| 2rh |
264 | 264 |
| And, 2rh = 264 h = |
|
264 x | 7 | x | 1 | x | 1 | |
= 6m. |
| 22 | 2 | 7 |
 Required ratio = |
2r | = | 14 | = 7 : 3. |
| h | 6 |
Discussion:
23 comments Page 2 of 3.
Mustafa said:
8 years ago
Not understanding, Please someone explain me.
Lokesh said:
8 years ago
@Goki.
we know radius =diameter/2,so diameter d =2r.
we know radius =diameter/2,so diameter d =2r.
Pramesh said:
8 years ago
Formula:
curved surface area(CSA) of a cylinder = 2πrh.
Volume(V) of a cylinder = π*r*r*h.
Given :
CSA = 264 .
V = 924.
Solution :
CSA = 2πrh = 264.
V = π*r*r*h = 924.
To find r, let us divided volume by CSA.
π*r*r*h/2πrh = 924/264.
After cancelling π, h, r, we get,
r = 2 * (924/264),
So, r = 7.
Subsitute value of r in 2πrh to find the value of h.
2πrh = 264 (given)
2 * 3.14 * 7 * h = 264.
On solving h = 6.
Now, diameter = 2 * r.
Diameter = 2 * 7 = 14.
Height = 6.
Ratio is 14/6 = 14 : 6 = 7 : 3.
curved surface area(CSA) of a cylinder = 2πrh.
Volume(V) of a cylinder = π*r*r*h.
Given :
CSA = 264 .
V = 924.
Solution :
CSA = 2πrh = 264.
V = π*r*r*h = 924.
To find r, let us divided volume by CSA.
π*r*r*h/2πrh = 924/264.
After cancelling π, h, r, we get,
r = 2 * (924/264),
So, r = 7.
Subsitute value of r in 2πrh to find the value of h.
2πrh = 264 (given)
2 * 3.14 * 7 * h = 264.
On solving h = 6.
Now, diameter = 2 * r.
Diameter = 2 * 7 = 14.
Height = 6.
Ratio is 14/6 = 14 : 6 = 7 : 3.
(1)
Rabia araf said:
8 years ago
Thanks.
Atush said:
8 years ago
Thanks.
Ruhi said:
8 years ago
How did you find h? Please explain.
Anushka said:
8 years ago
I didn't understand. Help me please.
Sathish said:
8 years ago
Why 2r/h comes for ratio? Please explain the step.
(2)
Hifi said:
7 years ago
Thanks for explaning the answer.
DINESH said:
6 years ago
Why not take 264/924?
Means surface area/volume. Please explain.
Means surface area/volume. Please explain.
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