A jet boat is used to take canoers 200 miles upriver to their starting point. As the driver of the jet boat, Jeremy knows that i
t will take him 5 hours to get the canoers upstream, but only 4 hours to get the boat back downstream after dropping the canoers off, as long as he keeps the boat moving at a constant speed.
200/5 = 40 mph 200/4 = 50 mph Let x be the speed in still waters and y the speed of current. x + y = 50 x - y = 40 ADD 2x = 90 x = 45 mph ANSWER is C) 2) C
