Okay, I think what you are actually asking is:
cars traveled equal distances in different amounts of time. Car A
traveled the distance in 2.4 h, and Car B traveled the distance in 4 h.
Car A traveled 22 mph faster than Car B, how fast did Car A travel?
It comes down to equations and that really is not my strong point (that really is an understatement!) but I have friends called google and Siri who are way more intelligent than I am so I have the answer. However, I have no idea how 'I' arrived there so please don't expect a breakdown of it, equations bring me out in a cold sweat at the best of times!
My maths teacher would be so proud! :-) I think what we are saying is that car A was traveling at 33 mph and I hope that answers your question and helps.