Question 598485:  There are two small valves in the bottom of a tub filled with water.  If opened, one valve will empty the tub in 3 hours; the other will empty it in 6 hours.  If both valves are opened at the same time, how long will it take to empty the tub?  Please show work.
 
 
 
I have such a problem with algebra.  I will appreciate any help you can give me.
 
 
 
Thank you, 
Lynnette 
 Found 2 solutions by  nerdybill, Alan3354: Answer by nerdybill(7384)      (Show Source): 
You can  put this solution on YOUR website! There are two small valves in the bottom of a tub filled with water. If opened, one valve will empty the tub in 3 hours; the other will empty it in 6 hours. If both valves are opened at the same time, how long will it take to empty the tub? Please show work.  
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Let t = time (hours) to empty tub by both valves 
then 
t(1/3 + 1/6) = 1 
multiplying both sides by 6, we get: 
t(2 + 1) = 6 
t(3) = 6 
t = 6/3 
t = 2 hours 
 Answer by Alan3354(69443)      (Show Source): 
You can  put this solution on YOUR website! There are two small valves in the bottom of a tub filled with water. If opened, one valve will empty the tub in 3 hours; the other will empty it in 6 hours. If both valves are opened at the same time, how long will it take to empty the tub? Please show work.  
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One drains 1/3 tank/hr 
The other drains 1/6 tank/hr 
Together, they drain 1/3 + 1/6 tank/hr = 1/2 tank/hour 
--> 2 hours per tank
 
 
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