document.write( "Question 1111099: Two cars, A and B, 148 kilometers apart, traveled toward each other. A started at 6 a.m. while B started an hour later. They met on the road at 9 a.m. Had both of them started at 6 a.m., they would have met at 8:28. Find the speed. \n" ); document.write( "
Algebra.Com's Answer #726117 by ikleyn(52850) You can put this solution on YOUR website! . \n" ); document.write( " \r\n" ); document.write( "1. In the first scenario, 1-st car was on the way 3 hours (from 6 am till 9 am) before meeting.\r\n" ); document.write( "\r\n" ); document.write( " 2-nd car was on the way 2 hours before meeting.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " Let \"a\" and \"b\" be their rates in miles per MINUTE, respectively. \r\n" ); document.write( "\r\n" ); document.write( " Then from the first scenario, the total distance between the cities was\r\n" ); document.write( "\r\n" ); document.write( " 180a + 120b = 148 miles. (1) (3 hours = 180 minutes; 2 hours = 120 minutes !)\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "2. In the second scenario, each car was on the way 2 hours and 28 minutes = 148 minutes. \r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " Therefore, the second equation for the entire distance is\r\n" ); document.write( "\r\n" ); document.write( " 148a + 148b = 148 miles, or\r\n" ); document.write( "\r\n" ); document.write( " a + b = 1 (miles per minute) (2) \r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "3. Thus you have this system of two equations in two unknowns\r\n" ); document.write( "\r\n" ); document.write( " a + b = 1, and\r\n" ); document.write( "\r\n" ); document.write( " 180a + 120b = 148.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( " Solve it by ANY method you want. Both methods - Substitution and Elimination - are good. Choose any and complete the solution on your own.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "4. H a p p y s o l v i n g ! !\r\n" ); document.write( "\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |