Larry C. answered 01/12/19
Computer Science and Mathematics professional
For these kinds of questions, they are easier to answer if you include units in the equation and add in the various conversions so that all the units cancel out except for the ones you want in the answer. So, since we have feet/second to start with and want to wind up with miles/hour:
242.0055 feet/2 seconds * 1 mile/5280 feet * 60 seconds/minute * 60 minutes/hour =
(242.0055*60*60)/(2 * 5280) miles/hour = 871,219.8/10,560 miles/hour = 82.5 miles/hour rounded