Question 1197471
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<pre>

Use the formula for average speed for any round trip


    {{{V[average]}}} = {{{(2*V[1]*V[2])/(V[1]+V[2])}}} = {{{(2*24*16)/(24+16)}}} = 19.2 mph.    <U>ANSWER</U>
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Solved.


About this formula, &nbsp;and to see other similar solved problems, &nbsp;look into 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>  

at this site.



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Regarding the opinions of other tutors, &nbsp;expressed in their posts, &nbsp;I can only say that, &nbsp;when I attended my middle school, 

knowing of this formula and knowing of its roots, &nbsp;as well as an ability to deduce it and to use it consciously was a &nbsp;{{{highlight(highlight(MANDATORY))}}}.



Twenty years after school, &nbsp;you may forget it; &nbsp;but while at the school, you &nbsp;MUST &nbsp;know it.



Also, &nbsp;think a minute about this: &nbsp;how will you solve this problem, &nbsp;if the given rates are not integer numbers, &nbsp;but are the decimal, &nbsp;instead ?


Will you find their common multiple then ?