document.write( "Question 1022112: Jenny and Penny can eat a whole gallon of ice cream together in 2 hours. Penny and Lenny can eat a whole gallon of ice cream together in 1 2/3 hours. All three together can eat a whole gallon of ice cream together in 1 hour. How many hours would it take Jenny to eat a whole gallon of ice cream all by herself? \n" ); document.write( "

Algebra.Com's Answer #637934 by ikleyn(52803) $\"\"$ $\"About$

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\n" ); document.write( "Jenny and Penny can eat a whole gallon of ice cream together in 2 hours.
\n" ); document.write( "Penny and Lenny can eat a whole gallon of ice cream together in 1 2/3 hours.
\n" ); document.write( "All three together can eat a whole gallon of ice cream together in 1 hour.
\n" ); document.write( "How many hours would it take Jenny to eat a whole gallon of ice cream all by herself?
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document.write( "Let j = time for Jenny to eat a whole gallon of ice cream all by herself\r\n" );
document.write( "    p = time for Penny - - - - \" - - - \r\n" );
document.write( "    y = time for Lenny.\r\n" );
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document.write( "Then from the condition you have these three equations (standard equations for rates)\r\n" );
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document.write( " +       = ,    (1)\r\n" );
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document.write( "      +  = ,    (2)     ( <---  = 1 :  )\r\n" );
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document.write( " +  +  = .    (3)\r\n" );
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document.write( "Now distract (2) from (3) (both sides). You will get \r\n" );
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document.write( " =  = .\r\n" );
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document.write( "Hence, j =  =  hours.\r\n" );
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document.write( "Answer. It will take  hours for Jenny to eat a whole gallon of ice cream all by herself.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Notice: The equation (1) was not used in the solution at all.
\n" ); document.write( " The corresponding part of the condition is not necessary and is excessive. \r
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\n" ); document.write( "\n" ); document.write( "Here I simply summarized the discussion that we, the three tutors, had on this problem in
\n" ); document.write( "http://www.algebra.com/algebra/homework/coordinate/word/Linear_Equations_And_Systems_Word_Problems.faq.question.1022114.html.\r
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