document.write( "Question 1199443: The distance covered by a rolling object at intervals of 1 second were recorded as 4 cm, 16 cm, 28 cm, 40 cm, etc. After how long will the object be 22.6m from the starting point?
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Algebra.Com's Answer #833354 by ikleyn(52781) $\"\"$ $\"About$

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\n" ); document.write( "The distance covered by a rolling object at intervals of 1 second were recorded
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document.write( "I interpret the given distances as the distances from the starting point\r\n" );
document.write( "at the time moments t= 1s, 2s, 3s, 4s and so on.\r\n" );
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document.write( "Notice that  first second the increment of the distance \r\n" );
document.write( "from the starting point is the same: it is 12 cm for every 1 second.\r\n" );
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document.write( "So, we can assume that after first second the movement is uniform with the constant speed of 12 cm/s.  \r\n" );
document.write( "    (Without making this assumption, we can not answer the question, at all).\r\n" );
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document.write( "Ok.  But if consider the movement from the starting time moment t= 0, \r\n" );
document.write( "     the movement IS NOT UNIFORM.\r\n" );
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document.write( "So, in order for the solution be correct, we should consider time interval AFTER 1 second:  t >= 1 second.\r\n" );
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document.write( "Under this consideration, the object will cover the distance from the mark of 4 cm \r\n" );
document.write( "to the mark of 22.6 m (= 2260 cm) in\r\n" );
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document.write( "         = 188 seconds.\r\n" );
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document.write( "To answer the problem's question, I must add 1 second to 188 seconds\r\n" );
document.write( "to account for the very first second and very first 4 cm.\r\n" );
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document.write( "So, the ANSWER is  1 + 188 = 189 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( "Surely, it can be solved in many different ways, but ALL SUCH SOLUTIONS
\n" ); document.write( "must account for the fact that the movement is not uniform in whole.\r
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\n" ); document.write( "\n" ); document.write( "It is uniform (or can be assumed uniform) only AFTER first second.\r
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\n" ); document.write( "\n" ); document.write( "This problem is to check and to train attentiveness of a student.\r
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\n" ); document.write( "\n" ); document.write( "In other words, the problem has a huge underwater stone (a trap),
\n" ); document.write( "and the meaning of a solution is to recognize this trap and to avoid falling in it.\r
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