document.write( "Question 286901: Can you please help me to set up this word problem and solve? Thank you.\r
\n" ); document.write( "\n" ); document.write( "At Four Mile Island, there are two pipes that carry water to the nuclear reactor chamber. The first pipe can fill the reactor chamber in 4 minutes; the second pipe can fill the reactor chamber in 6 minutes. The drain can empty the reactor chamber in 12 minutes. How long will it take both pipes to fill the chamber if the drain is left open? \n" ); document.write( "
Algebra.Com's Answer #208054 by ptaylor(2198)\"\" \"About 
You can put this solution on YOUR website!
Let x=amount of time it takes both pipes to fill the chamber if the drain is left open
\n" ); document.write( "With the drain open, both pipes fill at the rate of 1/x chamber per min
\n" ); document.write( "First pipe fills at the rate of 1/4 chamber per min
\n" ); document.write( "2nd pipe fills at the rate of 1/6 chamber per min
\n" ); document.write( "But the drain empties at the rate of 1/12 chamber per min
\n" ); document.write( "So, with the drain open, both pipes fill at the rate of
\n" ); document.write( "1/4 + 1/6 - 1/12 chamber per min. Our equation to solve then is:
\n" ); document.write( "1/4 + 1/6 - 1/12=1/x multiply each term by 12x
\n" ); document.write( "3x+2x-x=12
\n" ); document.write( "4x=12
\n" ); document.write( "x=3 min----amount of time it takes both pipes to fill the chamber if the drain is left open\r
\n" ); document.write( "\n" ); document.write( "CK
\n" ); document.write( "in 3 min first pipe fills (1/4)*3=3/4 chamber
\n" ); document.write( "in 3 min 2nd pipe fills (1/6)*3=1/2 chamber
\n" ); document.write( "in 3 min drain empties (1/12)*3=1/4 chamber
\n" ); document.write( "3/4 + 1/2 - 1/4 should equal 1 (1 chamber, that is)
\n" ); document.write( "3/4 + 2/4 -1/4=4/4=1
\n" ); document.write( "1=1\r
\n" ); document.write( "\n" ); document.write( "Hope this helps---ptaylor \n" ); document.write( "
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