Marcus drove from New York toward Chicago at a constant rate of 45 mph. Marie left New York 2 hr. later and drove the same route at 55 mph. How long was Marcus driving before Marie caught up?

Explanation:

Let the time of travel of Marcus before they caught up be t.

Time of travel of Marie = t - 2

Speed of Marcus = 45 mph

Speed of Marie = 55 mph

Distance traveled by them will be same.

Hence

Speed of Marcus x Time of travel of Marcus before they caught up= Speed of Marie x Time of travel of Marie before they caught up

          45 x t= 55 x (t-2)

          45t= 55 t - 110

           10 t = 110

               t = 11 hours

Marcus was traveling 11 hours before Marie caught up.

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