medals please help i got and hour please help

Troy was trying to catch up with the rest of his group, who had left earlier on a kayaking trip. Troy paddled 8 hours downstream, covering 72 miles before realizing that he had passed his group’s campground. He had to paddle back upstream for 18 miles to get back to his group’s campground. If the trip back upstream took Troy 6 hours, how fast was the river flowing (in mph)?

Question

medals please help i got and hour please help
 
Troy was trying to catch up with the rest of his group, who had left earlier on a kayaking trip. Troy paddled 8 hours downstream, covering 72 miles before realizing that he had passed his group’s campground. He had to paddle back upstream for 18 miles to get back to his group’s campground. If the trip back upstream took Troy 6 hours, how fast was the river flowing (in mph)?

anonymous · Answer

please help