document.write( "Question 1088379: A and B walk around a circular track . A and B walk at a speed of 2 rounds per hour and 3 rounds per hours respectively . If they start at 8 AM from the same point in opposite directions, how many times shall they cross each other before 9 30 AM ? \n" ); document.write( "

Algebra.Com's Answer #702673 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "A and B walk around a circular track. A and B walk at a speed of 2 rounds per hour and 3 rounds per hours respectively.
\n" ); document.write( "If they start at 8 AM from the same point in opposite directions, how many times shall they cross each other before 9 30 AM ?
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document.write( "1.  Let answer first more simple question:\r\n" );
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document.write( "        if they start from the same point in opposite directions at 8 am, when they meet each other next time ?\r\n" );
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document.write( "    It is clear that they will meet each other next time when the sum of distances covered by each along the circumference \r\n" );
document.write( "    becomes EXACTLY equal to one circle  length.\r\n" );
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document.write( "    Next, the rate of A is 2 rounds per hour; the rate of B is 3 rounds per hour;\r\n" );
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document.write( "    HENCE, their relative speed is (2+3) = 5 rounds per hour.\r\n" );
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document.write( "    So, they meet each other next time in 12 minutes = , \r\n" );
document.write( "        at 8:12 am.\r\n" );
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document.write( "2.  From his point, it is clear that they will meet each other EVERY 12 minutes.\r\n" );
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document.write( "    Now, how much room there is in 90 minutes for 12 minute intervals ?\r\n" );
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document.write( "    It is easy question:  = 7.5 times.\r\n" );
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document.write( "3.  So, if you start count from 8:00 when A and B are close to each other for the first time, you will count 7 times more when they meet each other.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Hope I answered your question.\r
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\n" ); document.write( "\n" ); document.write( "Similar problems are considered at the lesson\r
\n" ); document.write( "\n" ); document.write( " - Problems on bodies moving on a circle\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
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