Help understanding how to set up this word problem and why is is set up that way for a better understanding of how to do future word problems.

Question 6 1 pts Two automobiles are 150 kilometers apart and traveling toward each other. One automobile is moving at 60 km/h and the other is moving at 40 km/h. In how many hours will they meet? O 1.25 hours O 1.50 hours O 1.75 hours O 2.00 hours O 2.50 hours