document.write( "Question 1208236: Hi
\n" ); document.write( "David jogged for 5 days in a row. Each day he jogged 1.4km more than the day before. At the end of 5 days he jogged a total of 20.6km. How far did he jogged on the 5th day. \n" ); document.write( "

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\n" ); document.write( "David jogged for 5 days in a row. Each day he jogged 1.4km more than the day before.
\n" ); document.write( "At the end of 5 days he jogged a total of 20.6km. How far did he jogged on the 5th day.
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\n" ); document.write( "\n" ); document.write( " Consider this simple way solving.\r
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document.write( "The average distance, which David jogged per day, is   = 4.12 kilometers.\r\n" );
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document.write( "Intuitively, it is clear that this average distance is the distance which David jogged on the 3rd day\r\n" );
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document.write( "(3rd term is the central term of an arithmetic sequence of 5 terms).\r\n" );
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document.write( "From here, we conclude that on the 4th day David jogged 4.12 + 1.4 = 5.52 kilometers,\r\n" );
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document.write( "                            on the 5th day David jogged 5.52 + 1.4 = 6.92 kilometers.    ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved mentally without using any equations.\r
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\n" ); document.write( "\n" ); document.write( "To me, the entire educational meaning of this problem for a student is to find a straightforward
\n" ); document.write( "simplest way to solve to the end, avoiding long boring calculations and long boring reasoning.\r
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\n" ); document.write( "\n" ); document.write( "One brilliant idea dissects the problem and solves it instantly.\r
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