document.write( "Question 899640: A salesperson purchased an automobile that was advertised as averaging 27 mi/gal in the city and 38 mi/gal on the highway. A recent sales trip that covered 1192 miles required 36 gallons of gasoline. Assuming that the advertised mileage estimates were correct, how many miles were driven in the city? \n" ); document.write( "
Algebra.Com's Answer #545550 by josgarithmetic(39617)\"\" \"About 
You can put this solution on YOUR website!
This is Uniform Rates for fuel efficiency.
\n" ); document.write( "R = fuel efficiency
\n" ); document.write( "V = volume of fuel in gallons
\n" ); document.write( "D = distance in miles
\n" ); document.write( "RV=D\r
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\n" ); document.write( "\n" ); document.write( "A data table might help.\r
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\n" ); document.write( "\n" ); document.write( "___________________rate_________volume__________distance
\n" ); document.write( "CITY________________27
\n" ); document.write( "HIWAY_______________38
\n" ); document.write( "TOTALS___________________________36______________1192\r
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\n" ); document.write( "\n" ); document.write( "Use the basic equation to help fill the missing volume and distance data; assign variables, either for the volumes, or the distances. In fact, you could assign variables just to either the City or to the Highway. \r
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\n" ); document.write( "\n" ); document.write( ".(---Portion Cut Out and Moved Below, bottom of page field---)\r
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\n" ); document.write( "\n" ); document.write( "ASSIGNING VARIABLES DIFFERENTLY
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\n" ); document.write( "___________________rate_________volume__________distance
\n" ); document.write( "CITY________________27___________c/27_______________c
\n" ); document.write( "HIWAY_______________38___________h/38_______________h
\n" ); document.write( "TOTALS___________________________36______________1192\r
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\n" ); document.write( "\n" ); document.write( "Form two equations.
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\n" ); document.write( "\"c%2F27%2Bh%2F38=36\"
\n" ); document.write( "LCD=2*2*3*3*3*19
\n" ); document.write( "\"76c%2B54h=73872\"
\n" ); document.write( "-
\n" ); document.write( "\"c%2Bh=1192\"
\n" ); document.write( "-
\n" ); document.write( "\"highlight_green%28system%2876c%2B54h=73872%2Cc%2Bh=1192%29%29\"
\n" ); document.write( "Multiply the c+h equation by 54, subtract from the 76c+54h equation.
\n" ); document.write( "\"76c%2B54h-%2854c%2B54h%29=73872-54%2A1192\"
\n" ); document.write( "\"22c=9504\"
\n" ); document.write( "\"c=9504%2F22\"
\n" ); document.write( "\"highlight%28highlight%28c=432%29%29\", miles of city driving.\r
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\n" ); document.write( "\n" ); document.write( "-----------THIS ATTEMPT HAS UNKNOWN MISTAKE--------
\n" ); document.write( "This attempt will be to JUST assign c = distance done for the city.
\n" ); document.write( "The reason is that the question asks specifically for this.\r
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\n" ); document.write( "\n" ); document.write( "___________________rate_________volume____________________distance
\n" ); document.write( "CITY________________27___________c/27_______________________c
\n" ); document.write( "HIWAY_______________38__________(1192-c)/38_________________1192-c
\n" ); document.write( "TOTALS___________________________36_________________________1192\r
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\n" ); document.write( "\n" ); document.write( "That single variable assigning appears to be workable for a solution. The equation to solve will be \"highlight_green%28c%2F27%2B%281192-c%29%2F38=36%29\".\r
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\n" ); document.write( "\n" ); document.write( "The denominators are a bit inconvenient.
\n" ); document.write( "3*3*3, 2*19, 2*2*3*3
\n" ); document.write( "Lowest Common Denominator is \"highlight_green%282%2A2%2A3%2A3%2A3%2A19%29\", and most easily used in this factored form. Multiply left and right members by this.\r
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\n" ); document.write( "\n" ); document.write( "\"4%2A19%2Ac%2B%281192-c%29%2A3%2A3%2A3%2A2=3%2A19\"
\n" ); document.write( "\"76c%2B54%2A1192-54c=57\"
\n" ); document.write( "22c---------------------------------AND THE SOLUTION IS FAILING BECAUSE MAKES A NEGATIVE VALUE FOR c
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