document.write( "Question 522320: two cars (car 1 and car 2) are driving down the highway. Car 1 is moving at 60 miles per hour. Car 2 is driving at 70 miles per hour . Car 1 is starting 40 miles ahead of car 2 .How long will it take car 2 to catch up to car 1.
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Algebra.Com's Answer #346781 by Edwin McCravy(20059) $\"\"$ $\"About$

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two cars (car 1 and car 2) are driving down the highway. Car 1 is moving at 60 miles per hour. Car 2 is driving at 70 miles per hour . Car 1 is starting 40 miles ahead of car 2 .How long will it take car 2 to catch up to car 1.
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document.write( "Without algebra in your head:\r\n" );
document.write( "For car 2 to make up the 40 mile distance at an approach rate of 70-60 or 10mph\r\n" );
document.write( "will of course take 4 hours.\r\n" );
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document.write( "By algebra:  \r\n" );
document.write( "Make this chart:\r\n" );
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document.write( "         Distance     Rate    Time\r\n" );
document.write( "Car 1                           \r\n" );
document.write( "Car 2                           \r\n" );
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document.write( "Let the time for both be x hours:\r\n" );
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document.write( "         Distance     Rate    Time\r\n" );
document.write( "Car 1                           x\r\n" );
document.write( "Car 2                           x\r\n" );
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document.write( "Fill in the given rates (speeds):\r\n" );
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document.write( "         Distance     Rate    Time\r\n" );
document.write( "Car 1                  60       x\r\n" );
document.write( "Car 2                  70       x\r\n" );
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document.write( "Use Distance = rate × time to fill in the\r\n" );
document.write( "distances:\r\n" );
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document.write( "         Distance     Rate    Time\r\n" );
document.write( "Car 1      60x         60       x\r\n" );
document.write( "Car 2      70x         70       x\r\n" );
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document.write( "The equation comes from the fact that Car 2 will have \r\n" );
document.write( "to travel 40 miles more than Car 1 in order to catch up.\r\n" );
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document.write( "           =  + 40 miles\r\n" );
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document.write( "              70x = 60x + 40\r\n" );
document.write( "              10x = 40\r\n" );
document.write( "                x = 4 hours\r\n" );
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document.write( "Edwin

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