document.write( "Question 1117460: the hot water faucet can fill a bathtub in 9 min and the cold water faucet can fill the bathtub in 12 min. the drain can empty the bathtub in 18 min. if the bathtub is empty, how long will it take to fill the bathtub if both hot and cold faucets are on and the drain is open??? \n" ); document.write( "

Algebra.Com's Answer #732546 by solver91311(24713) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "If the hot water tap can fill the bathtub in 9 minutes, then the hot water tap must fill

of the bathtub in one minute. Likewise, the cold tap fills

of the tub in one minute and the drain empties

of the tub in one minute. So altogether:\r
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\n" ); document.write( "\n" ); document.write( "of the tub gets filled (because this is clearly a positive number) every minute, and it will take the reciprocal of the above sum in minutes to fill the tub, so since the lowest common denominator is 36:\r
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\n" ); document.write( "\n" ); document.write( "It will take

minutes or 7 minutes and 12 seconds to fill the tub if both taps and the drain are open.\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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