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Question

a container ship left Port 47 and traveled toward dry dock at an average speed of 10  km/h. A cruise ship left sometime later traveling in the same direction at an average speed of 25 km/h. After traveling for four hours the cruise ship caught up with the container ship. How long did the container ship travel before the cruise ship caught up?

Answer 1

If the container ship started t hours before the cruise ship, then

10 * (t + 4) = 25 * 4

=> t = 6 hours. So the container ship travelled for 6+ 4 = 10 hours before the cruise ship caught up.