SOLUTION: A tank is filled with 2 pipes. The first pipe can fill the tank in 10 hrs. But after it has been opened for 3 1⁄2 hours, the second pipe is opened and the tank is filled up i

Algebra ->  Rate-of-work-word-problems -> SOLUTION: A tank is filled with 2 pipes. The first pipe can fill the tank in 10 hrs. But after it has been opened for 3 1⁄2 hours, the second pipe is opened and the tank is filled up i      Log On


   

Question 1055416: A tank is filled with 2 pipes. The first pipe can fill the tank in 10 hrs. But after it has been opened for 3 1⁄2 hours, the second pipe is opened and the tank is filled up in 4 hours more. How long would it take the second pipe alone to fill the tank? The two pipes have different diameters.
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
PIPE           RATE (TANKSWORTH/HOURS)     TIME       VOLUME

First          1/10                        3&1/2      (1/10)(3&1/2)
Second         1/x
Combined      1/10+1/x                     4          4((1/10)+1/x)


Examine the tabulated description for a few minutes.

First pipe filled some of the tank volume during 3&1/2 hours and then BOTH pipes continued to fill the rest of the tank's volume for 4 hours. This was filling of the whole 1 tank volume.

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