I have no idea how to solve this pls help

Question

Ms.Robinson Was raining down the street the speed limit was 72420.3 meters per hour. she told  the officer  she was only going 55 miles per hour was she right? Use dimensional analysis to explain

Answer 1

72420.3 meters per hour

(72420.3m/hr)  x  (1 mile/1609.34m) = 45 mi/hr