document.write( "Question 1092990: Car A takes 15 seconds to go once around a circular racetrack, and car B takes 25 seconds to go once around the same track. If the two cars begin racing from the same position at the same time, how many seconds will it take for car A to pass car B? \n" ); document.write( "

Algebra.Com's Answer #707607 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "Let D be the length of the track.\r\n" );
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document.write( "    (As you will see from the solution, the value of D does not participate in the solution; \r\n" );
document.write( "     so it does not matter even in which linear units we measure D).\r\n" );
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document.write( "Then  the speed of the faster track is  linear units per second,\r\n" );
document.write( "while the speed of the slower track is  linear units per second.\r\n" );
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document.write( "The condition that the faster car will pass/overtake the slower is that the faster car will travel the distance \r\n" );
document.write( "    exactly D units longer than the slower track, or\r\n" );
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document.write( " -  = D.\r\n" );
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document.write( "After canceling the factor D in both sides this equation takes the form\r\n" );
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document.write( " -  = 1.\r\n" );
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document.write( "Simplify and solve for \"t\".  First step is to multiply both sides by 75:\r\n" );
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document.write( "5t - 3t = 75 ====>  2t  = 75  ====>  t =  = 37.5 seconds.\r\n" );
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document.write( "Answer.  The faster car will pass/overtake the smaller car in 37.5 seconds.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "There is the lesson \r
\n" ); document.write( "\n" ); document.write( "    - Problems on bodies moving on a circle \r
\n" ); document.write( "\n" ); document.write( "in this site, where similar problem is solved and presented (Problem 2).\r
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\n" ); document.write( "\n" ); document.write( "Also, you have this free of charge online textbook in ALGEBRA-I in this site\r
\n" ); document.write( "\n" ); document.write( "    ALGEBRA-I - YOUR ONLINE TEXTBOOK.\r
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\n" ); document.write( "\n" ); document.write( "The referred lesson is the part of this textbook under the section \"Word problems\", the topic \"Travel and Distance problems\",\r
\n" ); document.write( "\n" ); document.write( "where you will find many other advanced and non-traditional Travel and Distance problems.\r
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\n" ); document.write( "\n" ); document.write( "Save the link to this online textbook together with its description\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Free of charge online textbook in ALGEBRA-I\r
\n" ); document.write( "\n" ); document.write( "https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson\r
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\n" ); document.write( "\n" ); document.write( "to your archive and use it when it is needed.\r
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\n" ); document.write( "Dear \"students\" !\r
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\n" ); document.write( "\n" ); document.write( "Today is a special day.\r
\n" ); document.write( "\n" ); document.write( "Today I solved 16 problems for you and got back 0 (zero, ZERO) \"thanks\" from you.\r
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\n" ); document.write( "\n" ); document.write( "It is the absolute record !
\n" ); document.write( "    It is just out of limits of my understanding !
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\n" ); document.write( "\n" ); document.write( "Thank you very much and wish you to think:   WHO ARE YOU . . . \r
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