<p>This question is from Grubers test p.864 #20</p>
<p>The figure above (just shows a 2ft by 6ft base tank and height is unknown) shows water in a tank whose base is 2 feet by 6 feet. If a rectangular solid whose dimensions are 1 foot by 1 foot by 2 feet is totally immersed in the water, how many inches will the water rise?</p>
<p>(A) 1/6
(B) 1
(C) 2
(D) 3
(E) 12</p>
<p>I put A but the correct answer is C, could someone please explain.</p>
<p>Ok, I got it, but I'm really crap at explaining!!</p>
<p>What you forgot to do is convert the feet into inches (I'm guessing that's why you arrived at 1/6 - what you actually got was 1/6 of a foot, not 1/6 of an inch. And as you know 1/6 of a foot is 2 inches!)</p>
<p>Here's what you do (i'm showing you the long way so that you understand what I'm doing):</p>
<p>The tank is 24 inches x 72 inches x unkown inches (the unknown length is not needed).</p>
<p>The rectangular solid is 12 x 12 x 24 inches, so it has a volume of 3456 inches squared.</p>
<p>You want to find out, if you added a volume of 3456 inches squared to the tank, how much the water would rise, so you do 3456/(24 x 72), which equals 2.</p>
<p>Here's the easier way of doing it:</p>
<p>1x1x2=2, which is the volume (in feet) of the solid.
2x6=12, which is the area of the bottom of the tank</p>
<p>So the water rises by 2/12 of a foot. Since there are 12 inches in a foot, the water rises by 2 inches ;)</p>
<p>Hopefully my crappy explanation is helpful ;)</p>
<p>thx i didnt get ur first explanation but i got ur second one :), and i think ur right i mighta meant 1/6 foot instead of inch which is 2 inches</p>
<p>Almost as Sci-Fry did.
Replace 1x1x2 solid with 2x6xh of the same volume so that it would perfectly fit the bottom of the tank. Since h=2/12=1/6, the solid will push water 1/6 foot (or 2 inches) up.</p>