Aptitude - Volume and Surface Area - Discussion
Discussion Forum : Volume and Surface Area - General Questions (Q.No. 3)
3.
A hall is 15 m long and 12 m broad. If the sum of the areas of the floor and the ceiling is equal to the sum of the areas of four walls, the volume of the hall is:
Answer: Option
Explanation:
2(15 + 12) x h = 2(15 x 12)
 h = |
180 | m = | 20 | m. |
| 27 | 3 |
 Volume = |
 |
15 x 12 x | 20 |  m3 |
= 1200 m3. |
| 3 |
Video Explanation: https://youtu.be/V8EQ1YIaH74
Discussion:
75 comments Page 2 of 8.
Subash said:
5 years ago
I am not getting this, Anyone help me to get it out.
(1)
Arya said:
1 decade ago
Surface area of a cuboid we have 2(l+b)*h
and surface area of cuboid is 2 (lb + bh + lh) sq. units
whats the difference in this..
which apply where??
and surface area of cuboid is 2 (lb + bh + lh) sq. units
whats the difference in this..
which apply where??
(1)
Lokesh said:
9 years ago
This is for your kind information,
Floor Area = 15 x 12 = 180 m.
Ceiling Area = 15 x 12 = 180 m.
Now, Sum of Floor & Ceiling Area = 180 + 180 m = 360 m.
As given in question that,
(Sum of Floor & Ceiling Area = Sum of Wall Area).
360 = 2(Hall Length x Hall Height) + 2(Hall Width x Hall Height).
360 = 2(15 x Hall Height) + 2(12 x Hall Height).
Here I consider Hall Height = h.
360 = 30h + 24h,
360 = 54h,
h = 360/54,
h = 20/3.
So, Hall Height = 20/3.
As we know,
Volume of Box = Length x Width x Height.
Volume of Box = 15 x 12 x 20/3.
Volume of Box = 1200 Cubic meter.
Floor Area = 15 x 12 = 180 m.
Ceiling Area = 15 x 12 = 180 m.
Now, Sum of Floor & Ceiling Area = 180 + 180 m = 360 m.
As given in question that,
(Sum of Floor & Ceiling Area = Sum of Wall Area).
360 = 2(Hall Length x Hall Height) + 2(Hall Width x Hall Height).
360 = 2(15 x Hall Height) + 2(12 x Hall Height).
Here I consider Hall Height = h.
360 = 30h + 24h,
360 = 54h,
h = 360/54,
h = 20/3.
So, Hall Height = 20/3.
As we know,
Volume of Box = Length x Width x Height.
Volume of Box = 15 x 12 x 20/3.
Volume of Box = 1200 Cubic meter.
(1)
Jay-r said:
8 years ago
Simple formula,
h= (l * b) / (l + b) thus,
h= (15 x 12) / (15 + 12)
h= (180) / (27),
h= 180/27.
Volume of rectangle = l * b * h
= 15 x 12 x 180/27,
= 1200 cubic meter.
h= (l * b) / (l + b) thus,
h= (15 x 12) / (15 + 12)
h= (180) / (27),
h= 180/27.
Volume of rectangle = l * b * h
= 15 x 12 x 180/27,
= 1200 cubic meter.
(1)
Geet said:
8 years ago
I cannot understand this! Please, anyone explain it.
SKSENA said:
9 years ago
Thanks for all the given explanation of the answer.
Ramesh said:
9 years ago
Thank for your explanation. @Sonu.
Eaj said:
9 years ago
Thanks @Lokesh.
Harsh said:
9 years ago
I cannot understand this. Someone help me.
Sudhir said:
9 years ago
I didn't understand this! please explain it clearly.
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