In order to do conversion on these types of problems.
1.You first have to determine the relationship and the current unit and the target unit which it will be converted into.
2.In this case feet to meters and seconds to minutes
3.Determine the conversion rate: 1mi =1609 m and 1 h = 3600 sec;
4.You first calculate: 1230 m x 1 mi/1609 m = 0.764 mi/s
5.Next, is the time which is 0.764 mi/s x 3600s/1hr = 2752.02 mi/h