4/5 of a mile in nine minutes, Express speed as a unit rate, in miles per hour.

16/3 mile/1 hour or 5.33miles/1 hour

Explanation:

1 hr = 60 min

1) find unit rate and multiply unit rate by 60

unit rate = 4/5 divided by 9 = 4/45 miles per min

4/45*60=16/3