Question

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)?


A.
2 mph
B.
3 mph
C.
6 mph
D.
9 mph

Answer 1

@xapproachesinfinity

Answer 2

@Nurali

Answer 3

so let b=speed of boat
c= speed of surrent

b+c= downstream
b-c=upstream

Answer 4

set up 2 equations

8(b+c)=72
6(b-c)=18

Answer 5

Hmm

Answer 6

so divide both sides by 8 in the first equation
and divide both sides by 6 in the second equaiton

Answer 7

and multiply one of the equation by -1
then u can use elimination and solve for c

Answer 8

ur answer is 3 mph

Answer 9

Ohhh!!!