Answer:
They are running 7 1\5 miles per hour.
Step-by-step explanation:
You first turn the mixed number into a improper fraction which is 9/5. Then if 9\5 miles is equal to 1/5 of an hour you need to add 4 to 1/5 to get 5/5 which equals one hour. Then you multiply 4 to 9/5 to get your answer of 36/5, then just turn the improper fraction to a mixed number of 7 1\5 miles per hour.