A river cruise boat sailed 80 miles down the Mississippi River for 4 hours. It took 5 hours to return. Find the rate of the cruise boat in still water and the rate of the current.

Answer 1

r is the speed of the boat

s is the speed of the current

80/4 = 20 mph downstream

80/5 = 16 mph upstream

r+s = 20

r-s = 16

2r = 36

r = 18

s=2