document.write( "Question 257730: Can you walk me through this probably simple word problem: If I had the total gallons then I could determine this easier, so I am stumped:
\n" ); document.write( "\" The swimming pool can be filled in 12 hours with a pipe or 30 hours using a hose. How long will it take if both are used?\"\r
\n" ); document.write( "\n" ); document.write( "I want to say 21 hours but that would be too easy?? \n" ); document.write( "

Algebra.Com's Answer #189599 by jsmallt9(3758) $\"\"$ $\"About$

You can put this solution on YOUR website!
The key to these kinds of problems is to figure out how much of the total task can be done by each person/entity in one hour and then use these figures to solve the problem.

\n" ); document.write( "The pipe can do the entire task by itself in 12 hours. This means that the pipe can do 1/12 of the task in 1 hour.

\n" ); document.write( "The hose can do the entire task by itself in 30 hours. This means that the hose can do 1/30 of the task in 1 hour.

\n" ); document.write( "Working together the pipe and hose can do (1/12 + 1/30) of the task each hour.
\n" ); document.write( " $\"1%2F12+%2B+1%2F30+=+5%2F60+%2B+2%2F60+=+7%2F60\"$
\n" ); document.write( "Let x = the number of hours it takes both the pope and the hose to fill the pool. Then
\n" ); document.write( " $\"%287%2F60%29x+=+1\"$
\n" ); document.write( "Multiplying both sides by 60/7 we get:
\n" ); document.write( " $\"x+=+60%2F7+=+8%264%2F7\"$ \n" ); document.write( "

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