document.write( "Question 960284: a garden hose takes 180 minutes to fill up a hot tub, whereas it takes 300 minutes to drain it, if the drain is accidentally left open how long will it take to fill the hot tub? \n" ); document.write( "
Algebra.Com's Answer #586857 by Theo(13342)\"\" \"About 
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rate of filling is 1/180 of the tub in one minute.
\n" ); document.write( "rate of emptying is 1/300 of the tub in one minute.\r
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\n" ); document.write( "\n" ); document.write( "rate * time = quantity.
\n" ); document.write( "quantity is 1 full tub.
\n" ); document.write( "rate of filling and emptying work against each other, so their rates are subtractive.
\n" ); document.write( "time is what you want to find.\r
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\n" ); document.write( "\n" ); document.write( "equation becomes:\r
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\n" ); document.write( "\n" ); document.write( "(1/180 - 1/300) * T = 1
\n" ); document.write( "multiply both sides of this equation by 180 * 300 and you get:\r
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\n" ); document.write( "\n" ); document.write( "(300 - 180) * T = 180 * 300\r
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\n" ); document.write( "\n" ); document.write( "simplify to get:\r
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\n" ); document.write( "\n" ); document.write( "120 * T = 180 * 300\r
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\n" ); document.write( "\n" ); document.write( "divide both sides of this equation by 120 to get:\r
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\n" ); document.write( "\n" ); document.write( "T = 180 * 300 / 120\r
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\n" ); document.write( "\n" ); document.write( "simplify to get:\r
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\n" ); document.write( "\n" ); document.write( "T = 450 minutes.\r
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\n" ); document.write( "\n" ); document.write( "in 450 minutes, 450/180 = 2.5 times the tub has been filled and 450 / 300 = 1.5 times the tub has been emptied resulting in 1 full tub.\r
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\n" ); document.write( "\n" ); document.write( "every minute 1/180 of the tub is being filled and 1/300 of the tub is being empties, result in a net fill of 1/450 of the tub being filled.\r
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\n" ); document.write( "\n" ); document.write( "at that rate, the tub will be filled in 450 minutes.\r
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\n" ); document.write( "\n" ); document.write( "the solution checks out.\r
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