SOLUTION: Container A was filled with water to the brim. Then, some of the water was poured into an empty Container B until the height of the water in both containers was the same. Find th

Algebra ->  Volume -> SOLUTION: Container A was filled with water to the brim. Then, some of the water was poured into an empty Container B until the height of the water in both containers was the same. Find th      Log On


   



Question 1207330: Container A was filled with water to the brim. Then, some of the water was
poured into an empty Container B until the height of the water in both
containers was the same. Find the new height in both water containers.
Dimensions of container A: height=40, length= 25, width= 30
Dimensions of container B: height= unknown, length=25, width=18

Found 4 solutions by mananth, greenestamps, ikleyn, Edwin McCravy:
Answer by mananth(16946) About Me  (Show Source):
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Let x be the volume in A after pouring into B
Let y be the volume in B after pouring
Full volume in A = L*w*h =30000
x+y =30000
Volume in A after pouring
x = A*h
x = h*25*30
x = 750h
h = x/750

Volume in B = h *25*18
y = 450h
h= y/450
Heights are same after pouring
x/750 = y/450
x = y*750/450
x = 5y/3
x+y =30000 ( full volume in A)
substitute x
5y/ 3 + y = 30000

8y/3 = 30000
8y = 90000
y = 90000/8
y=11250 ( Volume in B after pouring)

x = 30000-11250
x=18750 (volume in A after pouring)
Volume / area = h
18750/750 = 25
Volume in B = 30000-18750 =11250
h= 11250/450 =25
Height same after pouring




Answer by greenestamps(13200) About Me  (Show Source):
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It's awkward to discuss the problem without units, so I will assume the given dimensions are centimeters.

The volume of water is the volume of container A, which is 40*25*30 = 30,000 cm^3.

Let x be the height (depth) of the water in the two containers after some of it is poured into container B.
Then the volume of water in container A is (25*30)*x = 750x
And the volume of water in container B is (25*18)*x = 450x

The volume of water in the two containers is the original 30,000 cm^3:

750x%2B450x+=+30000
1200x=30000
x=30000%2F1200=25

ANSWER: 25cm


Answer by ikleyn(52787) About Me  (Show Source):
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.

After pouring, the common height will be, obviously, the total volume divided by the total base area,
which is 25*30 + 25*18 = 1200 cm^2.


So, the answer is  the_volume_of_the_liquid%2Ftotal_base_area = %2825%2A30%2A40%29%2F1200 = %2825%2A1200%29%2F1200 = 25 cm.

Solved.



Answer by Edwin McCravy(20056) About Me  (Show Source):
You can put this solution on YOUR website!


When container A was filled with water to the brim, the volume of water in it
was lwh=(25)(30)(40). 

Then, some water from A was poured into B (when B was empty), until the height
of the water in both containers was the same. 

Let that common height be the unknown x.  

So the height of the water in A went down from 40 to x. Therefore the volume 
of water in A was reduced to lwh=(25)(30)x.

and

the height of the water in B went up from 0 to x. Therefore the volume of water
in B went up from 0 to lwh=(25)(18)x.

Then the sum of the volumes of water in both containers afterward was the same
amount of water as was in container A at the beginning, so we have an equation:

(25)(30)x + (25)(18)x = (25)(30)(40)

Solve that for x and you'll get the correct answer.

[Note. You may connect this problem to something you may have learned in your
science class as to how to get the water levels the same. Although the problem
says the water was 'poured' from A to B, a better (or at least more scientific)
way to get the levels the same would be to use a siphon.  A siphon is a water-
filled tube connecting the water in the two containers.  The water at the bottom
of A must support the heavy weight of all the water above it, so the upper water
in A will "push down" on the lower water in A forcing water to flow up the tube
from A into B.  The heavy upper water in A will continue to "push down" on the
lower water in A, forcing water up the tube from A into B, until the water
levels are the same.]     

Edwin