document.write( "Question 1155855: Bob was driving home at an average speed of 40mph for 2 hours. How fast should he drive for the next 1 hour to have an average speed of 50mph \n" ); document.write( "

Algebra.Com's Answer #778553 by josgarithmetic(39627) $\"\"$ $\"About$

You can put this solution on YOUR website!

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document.write( "                SPEED      TIME        DISTANCE\r\n" );
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document.write( "Was doing         40         2         40*2=80\r\n" );
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document.write( "Next hour         r          1           r\r\n" );
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document.write( "TOTALS                       3          r+80\r\n" );
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\n" ); document.write( "\n" ); document.write( "Want average speed , 50 mph.\r
\n" ); document.write( "\n" ); document.write( " $\"%28r%2B80%29%2F3=50\"$ \r
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\n" ); document.write( "\n" ); document.write( " $\"r%2B80=150\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"r=150-80\"$ \r
\n" ); document.write( "\n" ); document.write( " $\"r=70\"$ \n" ); document.write( "

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