Let x be the rate of the slower car, in miles per hour.

Then the rate of the faster car is (x+10) mph.


Then the total distance equation is


     = 208  miles.    <<<---===   is 1 hour and 36 minutes


To solve it, multiply by 60 both sides


    96x + 96x + 960 = 208*60

    192x = 208*60 - 960

    192x = 11520  ====>  x =  = 60 miles per hour.


Answer.  The slower car rate is 60 mph;  the faster car rate is 70 mph.