document.write( "Question 1144627: Two buses leave towns 732 km apart at the same time and travel toward each other. One bus travels 12 km/h slower than the other. If they meet in 3 hours, what is the rate of each bus? \n" ); document.write( "
Algebra.Com's Answer #765793 by Edwin McCravy(20054)\"\" \"About 
You can put this solution on YOUR website!
One bus travels 12 km/h slower than the other...
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document.write( "Let the faster bus's speed be r km/h.\r\n" );
document.write( "Then the slower bus's speed is r-12 km/h.\r\n" );
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\n" ); document.write( "...travel toward each other.
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document.write( "Since they travel toward each other, their speed of approach is the sum\r\n" );
document.write( "of their speeds, r + r-12 which is 2r-12 km/h\r\n" );
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\n" ); document.write( "...they meet in 3 hours,...
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document.write( "That means the distance between them goes from 732 km to 0 km in 3 hours.\r\n" );
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\n" ); document.write( "...what is the rate of each bus?
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document.write( "Distance = (rate)(time)\r\n" );
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document.write( "732 = (2r-12)(3)\r\n" );
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document.write( "Divide both sides by 3\r\n" );
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document.write( "244 = 2r-12\r\n" );
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document.write( "Add 12 to both sides\r\n" );
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document.write( "256 = 2r\r\n" );
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document.write( "Divide both sides by 2\r\n" );
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document.write( "128 = r\r\n" );
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document.write( "So the faster bus went 128 km/h\r\n" );
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document.write( "The slower bus went 128-12 or 116 km/h\r\n" );
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document.write( "That's really fast!  So let's check how far each\r\n" );
document.write( "went in 3 hours.\r\n" );
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document.write( "The faster bus went 128 km/h for 3 hours and therefore went (128)(3)=384 km.\r\n" );
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document.write( "The slower bus went 116 km/h for 3 hours and therefore went (116)(3)=348 km.\r\n" );
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document.write( "So their distances traveled until they met should add up to 732 km.  \r\n" );
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document.write( "And they do!:\r\n" );
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document.write( "384 km + 348 km = 732 km.\r\n" );
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document.write( "So the answers 128 and 116 km/h are correct. Hope they didn't get a ticket! lol\r\n" );
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document.write( "Edwin
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