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 7 of 8.
Prim said:
1 decade ago
@sonu thanks.
Sonu said:
1 decade ago
Yes the surface area of cuboid is 2(lb+bh+hl)
But surface area of 4 walls doesnot includes areas of floor+ceiling. thats why Total area of walls = 2(lb+bh+bl) - 2 (lb) = 2(hb+lh) = 2(b+l)h
But surface area of 4 walls doesnot includes areas of floor+ceiling. thats why Total area of walls = 2(lb+bh+bl) - 2 (lb) = 2(hb+lh) = 2(b+l)h
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??
Jordan said:
1 decade ago
Here given that
Area of four walls = (area of the base )+(area of ceiling)
Area of base is (l*b)
Area of ceiling is (l*b)
so (area of the base )+(area of ceiling)=2(l*b)
As per Surface area of a cuboid we have 2(l+b)*h
Area of four walls=2(l+b)*h
Area of four walls = (area of the base )+(area of ceiling)
Area of base is (l*b)
Area of ceiling is (l*b)
so (area of the base )+(area of ceiling)=2(l*b)
As per Surface area of a cuboid we have 2(l+b)*h
Area of four walls=2(l+b)*h
Jordan said:
1 decade ago
Here given that
Area of four walls = (area of the base )+(area of ceiling)
Area of base is (l*b)
Area of ceiling is (l*b)
so (area of the base )+(area of ceiling)=2(l*b)
As per Surface area of a cuboid we have 2(l+b)*h
Area of four walls=2(l+b)*h
Area of four walls = (area of the base )+(area of ceiling)
Area of base is (l*b)
Area of ceiling is (l*b)
so (area of the base )+(area of ceiling)=2(l*b)
As per Surface area of a cuboid we have 2(l+b)*h
Area of four walls=2(l+b)*h
Sreelakshmi said:
1 decade ago
Please explain this concept with proper steps.
Geethu said:
1 decade ago
2(15*12)=2(lh+bh)
=2h(l+b)
15*12 = h(15+12)
h=(15*12)/(15+12)=180/27
=2h(l+b)
15*12 = h(15+12)
h=(15*12)/(15+12)=180/27
Summi said:
1 decade ago
Hey can any one explain how you got 180/27cm ?
Yogarajan said:
1 decade ago
Hello, can any one clearly explain the basics of the concept please ?
Reshma said:
1 decade ago
Hello all,
I could not understand the first step of the explanation.
According to this site surface area of cuboid is 2 (lb + bh + lh) sq. units.
I could not understand the first step of the explanation.
According to this site surface area of cuboid is 2 (lb + bh + lh) sq. units.
Post your comments here:
Quick links
Quantitative Aptitude
Verbal (English)
Reasoning
Programming
Interview
Placement Papers