Question 1197471
<pre><font face = "consolas" color = "indigo" size = 3><b>
Hi  
A car covered a certain distance {{{d}}} at a speed of 24mph to  &  16mph back: 
  d = rt  0r d/r = t
Let x be the AVERAGE speed of the Entire trip {{{2d}}} 
 {{{d/(24mph) + d/(16mph) = 2d/x}}}   | divide each term by d
 {{{1/24 + 1/16 = 2/x}}}   | Multiply thru by 48x to solve 
     2x + 3x = 96
           x = 96/5 = 19.2,  the average speed of the car for the entire journey
</font></b></pre>