Hi, Damarys
With an average speed of 47 mph, and a distance of 230 miles; the simplest way I can explain is by using the train track methods.
230 miles x 1 hour / 47 m = 4.89 hours.
This way the miles will cancel and you left with hours.
The 47 mph is a conversion so it can also be rewritten as 1 hour / 47 miles.
I hope this help.
Please let me know if I can be help.
Tran
Damarys C.
thank you so much04/20/19