Question 1182366
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&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This problem &nbsp;TEACHES &nbsp;you &nbsp;<U>to distinct</U> &nbsp;between &nbsp;<U>average velocity</U> &nbsp;and &nbsp;<U>average speed</U> 


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(which in this problem is the same as average rate).



To calculate average speed &nbsp;(or average rate), &nbsp;you should take the total traveled distance and divide it by the full spent traveled time.



But &nbsp;THIS &nbsp;PROBLEM &nbsp;asks about the average <U>velocity</U>.


Velocity is the vector, &nbsp;in distinct of speed and of rate.


To calculate average velocity, &nbsp;you should take the &nbsp;<U>displacement vector</U> &nbsp;and divide it by the full spent traveled time.




&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In this problem, &nbsp;the displacement is &nbsp;THE &nbsp;DIFFERENCE &nbsp;&nbsp;200 yards &nbsp;&nbsp;MINUS &nbsp;&nbsp;50 yards = 200 - 50 = 150 yards


&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;and you should divide it by &nbsp;35 &nbsp;seconds.




So, &nbsp;the average velocity magnitude is  &nbsp;&nbsp;{{{(200-50)/35}}} = {{{150/35}}} = 4.286 yards per second.    &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<U>ANSWER</U>
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Solved and explained.