Question 1153814
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<pre>

There is a general formula


    {{{V[average]}}} = {{{(2*v[1]*v[2])/(v[1]+v[2])}}} 


for such problems.


Substitute your data into the formula and calculate.
</pre>

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An amazing fact is that (from this formula point of view), &nbsp;the average speed &nbsp;<U>DOES &nbsp;NOT &nbsp;depend</U> &nbsp;on the total distance (!)


It is &nbsp;THE &nbsp;SAME &nbsp;for any distance and any two-ways returning trip (!)


In this sense, the given distance is &nbsp;<U>IRRELEVANT &nbsp;(!) &nbsp;in this problem &nbsp;(!) &nbsp;(!)</U>


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See the lessons

&nbsp;&nbsp;&nbsp;&nbsp;- <A /HREF=http://www.algebra.com/algebra/homework/word/travel/Calculating-an-average-speed.lesson>Calculating an average speed: a train going from A to B and back</A> 

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/word/travel/One-more-problem-on-calculating-an-average-speed.lesson>One more problem on calculating an average speed</A>  

in this site.