Victoria is training for an upcoming triathlon and plans to run 12 miles today. Hermes offered to ride his bicycle to help her maintain her pace. If Victoria wants to keep a steady pace of 6.5 per mile per hour, how fast should Hermes ride in miles per hour?

I have no idea what "6.5 per mile per hour" means.

However, if you mean 6.5 minutes per mile, then
1mile/6.5min * 60min/hr = 60/6.5 mi/hr

Not sure where the 12 miles comes in ...