CAT 2018 Slot 1 QA Q23 Time, Speed & Distance

Question 23 of the Quantitative Ability (QA) section, CAT 2018 Slot 1, with CAT's official answer.

Train T leaves station X for station Y at 3 pm. Train S, traveling at three quarters of the speed of T, leaves Y for X at 4 pm. The two trains pass each other at a station Z, where the distance between X and Z is three-fifths of that between X and Y. How many hours does train T take for its journey from X to Y? [TITA]

TITA: type in the answer. There are no options and no negative marking.

Answer: 15 Time, Speed & Distance TITA

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