document.write( "Question 48347: Steve traveled 200 miles at a certain speed. Had he gone 10mph faster, the trip would have taken 1 hour less. Find the speed of his vehicle. \n" ); document.write( "
Algebra.Com's Answer #31989 by AnlytcPhil(1806)\"\" \"About 
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Steve traveled 200 miles at a certain speed. Had he gone 10mph faster,\r\n" );
document.write( "the trip would have taken 1 hour less. Find the speed of his vehicle.\r\n" );
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document.write( "Make a chart like this\r\n" );
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document.write( "                   DISTANCE   RATE       TIME\r\n" );
document.write( "Actual trip                                     \r\n" );
document.write( "Hypothetical trip                                \r\n" );
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document.write( "Let the speed of his vehicle be x\r\n" );
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document.write( "Then if he had gone 10 mph faster, his speed would have been x+10\r\n" );
document.write( "So we put x for the actual rate, and x+10 for the hypothetical rate\r\n" );
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document.write( "                   DISTANCE   RATE       TIME\r\n" );
document.write( "Actual trip                     x            \r\n" );
document.write( "Hypothetical trip             x+10                \r\n" );
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document.write( "We are told that his distance was 200, so we put 200 for\r\n" );
document.write( "the distances in both cases:\r\n" );
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document.write( "                   DISTANCE   RATE       TIME\r\n" );
document.write( "Actual trip           200       x            \r\n" );
document.write( "Hypothetical trip     200     x+10              \r\n" );
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document.write( "Now we use TIME = DISTANCE/RATE to fill in the two rates:\r\n" );
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document.write( "                   DISTANCE   RATE       TIME\r\n" );
document.write( "Actual trip           200       x       200/x\r\n" );
document.write( "Hypothetical trip     200     x+10    200/(x+10)\r\n" );
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document.write( "We are told that the time for the hypothetical trip was 1\r\n" );
document.write( "hour less, so \r\n" );
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document.write( "HYPOTHETICAL TIME = ACTUAL TIME - 1\r\n" );
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document.write( "      200/(x+10) = 200/x - 1\r\n" );
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document.write( "Can you solve that?  Hint: Multiply thru by LCD = x(x+10)\r\n" );
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document.write( "Answer: x = 40 mph\r\n" );
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document.write( "Edwin
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