document.write( "Question 1187574: Hello there. I need some help with the following word problem please and thank you in advance! \r
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document.write( "Rob Gronowski of the New England Patriots can run 100 yards in 12 seconds, and Matt Forte of the New York Jets can run 100 yards in 9 seconds. Suppose that Gronowski catches a pass at his own 20-yard line in stride and starts running away from Forte, who is at the 15-yard line directly behind Gronowski. At what yard line will Forte catch up to Gronowski? \n" );
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Algebra.Com's Answer #818591 by Theo(13342)![]() ![]() You can put this solution on YOUR website! rate * time = distance.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "for rob, the formula becomes r * 12 = 100 yards. \n" ); document.write( "for matt, the formula becomes r * 9 = 100 yards.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "solve for r to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "for rob, r = 100/12. \n" ); document.write( "for matt, r = 100/9.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "rob catches a pass at his own 20 yard line. \n" ); document.write( "matt is at the 15 yard line directly behind rob.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "in order to catch rob, matt has to run 5 more yards than rob in the same amount of time.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "let the distance that rob has to run equal to x. \n" ); document.write( "let the distance that matt has to run equal to x + 5. \n" ); document.write( "the time is the same for both.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the formula for rob becomes 100/12 * t = x \n" ); document.write( "the formula for matt becomes 100/9 * t = x + 5\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "subtract the first equation from the second to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "100/9 * t - 100/12 * t = 5.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "multiply both sides of this equation by (9 * 12) to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "100*12 * t - 100 * 9 * t = 5 * 9 * 12\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "simplify to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "1200 * t - 900 * t = 540\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "combine like terms to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "300 * t = 540\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "divide both sides of the equation by 300 to get:\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "t = 540 / 300 = 1.8\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "matt will catch up with rob in 1.8 seconds.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "rob starts at the 20 yard line and runs at the rate of 100/12 yards per second for 1.8 seconds.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "100/12 * 1.8 = rate * time = a distance of 15 yards. \n" ); document.write( "since he starts at the 20 yard line, he winds up at the 35 yard line.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "matt starts at the 15 yard line and runs at the rate of 100/9 yards per second for 1.8 seconds.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "100/9 * 1.8 = rate * time = a distance of 20 yards. \n" ); document.write( "since he starts at the 15 yard line, he winds up at the 35 yard line.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the 35 yard line is where matt catches up with rob.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |