document.write( "Question 1206959: Hi
\n" ); document.write( "Water is leaking fron a tank at a constant rate . At 230pm the tank is 3/5 full .At 325pm the tank was 2/7 full. At what time will the tank be empty.
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Algebra.Com's Answer #844725 by Edwin McCravy(20055) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "To make the fractions easy to use, suppose the tank holds 35 gallons, or\r\n" );
document.write( "35 of any unit of volume you choose.\r\n" );
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document.write( "At 2:30, the tank contains 21 gallons. (3/5 of 35)\r\n" );
document.write( "55 minutes later (at 3:25) the tank contains 10 gallons. (2/7 of 35).\r\n" );
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document.write( "So it leaked out 11 gallons in 55 minutes. (21-10)\r\n" );
document.write( "How long will it take to leak out those remaining 10 gallons?\r\n" );
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document.write( "Set up the proportion: (gallons over minutes equals gallons over minutes):\r\n" );
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document.write( "So 50 minutes after 3:25 is 4:15. \r\n" );
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document.write( "Here's an alternate way to get the answer without changing any of the\r\n" );
document.write( "original information (not the easiest way! LOL)\r\n" );
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document.write( "Let x = the number of hours after 12 noon or midnight\r\n" );
document.write( "Let y = the fraction of fullness the tank is at time x.\r\n" );
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document.write( "We want to know what x is when y = 0.\r\n" );
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document.write( "When its  hours past 12 noon or midnight, it's ths full.\r\n" );
document.write( "When its  hours past 12 noon or midnight, it's ths full.\r\n" );
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document.write( "So we want the equation of the line through the points:\r\n" );
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document.write( " and \r\n" );
document.write( "which is\r\n" );
document.write( " and \r\n" );
document.write( "which is\r\n" );
document.write( " and \r\n" );
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document.write( "Slope formula:\r\n" );
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document.write( "where (x₁,y₁) = \r\n" );
document.write( "and where (x₂,y₂) = \r\n" );
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document.write( "Multiply top and bottom by \r\n" );
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document.write( "Point-slope formula:\r\n" );
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document.write( "where (x₁,y₁) = \r\n" );
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document.write( "Substituting 0 for y, to find when tank is empty:\r\n" );
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document.write( "Multiply through by 35\r\n" );
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document.write( "So the tank became empty at 4 1/4 hours after 12 noon or midnight.\r\n" );
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document.write( "1/4 of an hour is 15 minutes\r\n" );
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document.write( "So the instant the tank became empty was at 4:15 PM or AM\r\n" );
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document.write( "Edwin

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