Question 1144626
.
<pre>

8*r + 8*(r+77) = 11208  miles.     


8r + 8r + 8*77 = 11208


16r            = 11208 - 8*77


16r            = 10592


 r             = 10592/16 = 662.


<U>ANSWER</U>.  The slower plane rate is 662 miles per hour.  The faster plane rate is  662+77 = 739 miles per hour.
</pre>