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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<pre>
I interpret the given distances as the distances from the starting point
at the time moments t= 1s, 2s, 3s, 4s and so on.


Notice that {{{highlight(after)}}} first second the increment of the distance 
from the starting point is the same: it is 12 cm for every 1 second.


So, we can assume that after first second the movement is uniform with the constant speed of 12 cm/s.  
    (Without making this assumption, we can not answer the question, at all).


Ok.  But if consider the movement from the starting time moment t= 0, 
     the movement IS NOT UNIFORM.


So, in order for the solution be correct, we should consider time interval AFTER 1 second:  t >= 1 second.


Under this consideration, the object will cover the distance from the mark of 4 cm 
to the mark of 22.6 m (= 2260 cm) in

        {{{(2260-4)/12}}} = 188 seconds.


To answer the problem's question, I must add 1 second to 188 seconds
to account for the very first second and very first 4 cm.


So, the <U>ANSWER</U> is  1 + 188 = 189 seconds.
</pre>

Solved.


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Surely, it can be solved in many different ways, &nbsp;but &nbsp;ALL &nbsp;SUCH &nbsp;SOLUTIONS
must account for the fact that the movement is not uniform in whole.


It is uniform &nbsp;(or can be assumed uniform) &nbsp;only &nbsp;AFTER &nbsp;first second.


This problem is to check and to train attentiveness of a student.


In other words, &nbsp;the problem has a huge underwater stone &nbsp;(a trap),
and the meaning of a solution is to recognize this trap and to avoid falling in it.