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A closed cylindrical tank contains 36pi cubic feet of water
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Updated on: 22 Oct 2013, 23:32
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A closed cylindrical tank contains 36pi cubic feet of water and is filled to half its capacity. When the tank is placed upright on its circular base on level ground, the height of the water in the tank is 4 feet. When the tank is placed on its side on level ground, what is the height, in feet, of the surface of the water above ground? A. 2 B. 3 C. 4 D. 6 E. 9 However what I see is a tank that has 36pi water in it that is half full. So total volume is 72pi. Since the water has height of 2 feet when placed on a circular base, that means the height of the entire cylinder is 4. 72pi/4 = 18pi pir^2 = 18pi r^2 = 18 r=3*sqrt(2) Where am I going wrong here? OPEN DISCUSSION OF THIS QUESTION IS HERE: aclosedcylindricaltankcontains36picubicfeetofwater134500.html
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Originally posted by bschoolnewbie2011 on 21 Feb 2012, 19:17.
Last edited by Bunuel on 22 Oct 2013, 23:32, edited 2 times in total.
Edited the typo: should be 4 feet instead of 2 feet.



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Re: Error in Official Guide Diagnostic #5?
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21 Feb 2012, 20:08
Ahh I see in the solution that the question say 4 for the height of the water instead of 2. So it was a typo.



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Re: Error in Official Guide Diagnostic #5?
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21 Feb 2012, 21:31
A closed cylindrical tank contains 36pi cubic feet of water and is filled to half its capacity. When the tank is placed upright on its circular base on level ground, the height of the water in the tank is 4 feet. When the tank is placed on its side on level ground, what is the height, in feet, of the surface of the water above ground?A. 2 B. 3 C. 4 D. 6 E. 9 Since the tank is half full when placed upright then naturally it'll also be half full when placed on its side, so the level of the water will be half of the diameter, so r. Now, given that \(V_{water}=\pi{*r^2}*H_{water}\) > \(36\pi=\pi{r^2}*4\) > \(r=3\). Answer: B.
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Re: A closed cylindrical tank contains 36pi cubic feet of water
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22 Feb 2012, 07:48
bunuel not understood why its half full when lying on level ground and why its height is 3 , radius = 3 even i got but how its height also 3, please explain. thanks



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Re: A closed cylindrical tank contains 36pi cubic feet of water
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22 Feb 2012, 08:20



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Re: A closed cylindrical tank contains 36pi cubic feet of water
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22 Feb 2012, 08:30
thanks, understood.



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Cylinder Volume Problem
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03 Apr 2012, 15:23
A closed cylindrical tank contains 36Pi cubic feet of water and is filled to half its capacity. When the tank is placed upright on its circular base on level ground, the height of the water in the tank is 4 feet. When the tank is placed on its side on level ground, what is the hight, in feet, of the surface of the water above the ground?
A) 2 B) 3 C) 4 D) 6 E) 9
I answered the problem correctly but I was wondering if it's just a "rule" that if the cylinder was filled half way, that if placed on its side, the water would still reach half the hight (i.e. the height of the radius). Is there a time when this wouldn't hold true?
Thanks, Rich



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Re: Cylinder Volume Problem
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03 Apr 2012, 16:51
Rich, what you're describing will always be true for a closed container of any shape. No matter the orientation, half (1/3, 1/4, etc) full never changes.
Miller Coors would have a big problem on their hands if a full can of beer somehow turned into a 3/4 can of beer upon a change in the can's orientation!



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Re: Cylinder Volume Problem
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03 Apr 2012, 19:34
nsspaz151 wrote: Rich, what you're describing will always be true for a closed container of any shape. No matter the orientation, half (1/3, 1/4, etc) full never changes.
Miller Coors would have a big problem on their hands if a full can of beer somehow turned into a 3/4 can of beer upon a change in the can's orientation! Let me clarify. For example, let's take a rectangular prism with: length = 10 width = 2 depth = 3 If I fill the prism half full (V = 30 units^3) and place it on its face with the smallest sides (2 x 3), the height would be 5 or length/2. However, if I place the prism flat on the largest side (10 x 3), the height would have to be 1. I hope that better illustrates the problem that I'm having...



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Re: Cylinder Volume Problem
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03 Apr 2012, 22:43
NvrEvrGvUp wrote: A closed cylindrical tank contains 36Pi cubic feet of water and is filled to half its capacity. When the tank is placed upright on its circular base on level ground, the height of the water in the tank is 4 feet. When the tank is placed on its side on level ground, what is the hight, in feet, of the surface of the water above the ground?
A) 2 B) 3 C) 4 D) 6 E) 9
I answered the problem correctly but I was wondering if it's just a "rule" that if the cylinder was filled half way, that if placed on its side, the water would still reach half the hight (i.e. the height of the radius). Is there a time when this wouldn't hold true?
Thanks, Rich Merging similar topics. I think your question is answered above.
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Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
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Re: A closed cylindrical tank contains 36pi cubic feet of water
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28 May 2012, 22:19
Had the container been 1/4th full with water,what would have been the answer?Diameter/4?



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Re: A closed cylindrical tank contains 36pi cubic feet of water
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30 May 2012, 12:02
EDIT: I just found out it's a print issue/their mistake. In my book (and the one in Google Books) the height given is 2, not 4 (OG Guide, 13th edition). So beware people, if your OG has 2 in the problem, then the solution given is wrong.Sorry for bumping this (and my first post on this forum) but I also can't see why the answer is 3. We have 2 scenarios here: vertical tank and horizontal tank. And we know this:  Volume of water: 36pi  Capacity of tank: 2*36pi  Height of water when tank is vertical: 2  Height of tank: 2*2  Height of water when tank is horizontal: r  Height of tank when tank is horizontal: 2*r So the formulas are in attachment. Now can someone explain to me how the hell the radius is 3? The solutions use this formula: 36pi = pi*r^2 * 4. But this formula must be wrong because if they are calculating for the vertical position then h = 2 and if they are calculating for the horizontal position then they must use half the area of the base in order to multiply with h = 4.
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Cylinder.PNG [ 54.67 KiB  Viewed 9436 times ]



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Re: A closed cylindrical tank contains 36pi cubic feet of water
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22 Oct 2013, 15:03
Dear GMAC,
I really hope you don't have typos like this on the actual GMAT... and this is a real retired question?
Please step up your game.
Your pal,
H



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Re: A closed cylindrical tank contains 36pi cubic feet of water
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22 Oct 2013, 23:33



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Re: A closed cylindrical tank contains 36pi cubic feet of water
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16 Oct 2018, 16:41
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Re: A closed cylindrical tank contains 36pi cubic feet of water
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