Passage

Directions to Solve In each of the questions below consists of a question and two statements numbered I II and III given below it. You have to decide whether the data provided in the statements are sufficient to answer the question.

What is the length of train 'A'? I. Train A takes 8 second to cross a pole II. Train A cross train B coming from opposite side in 8 second, speed of train B is 25 m/sec and length of train B is half of that of train A. III. Train A takes 10 sec to cross two poles 100 m apart.

Any two statements provide enough distinct equations to solve for the train's length and speed. Statements I and III both give crossing times for objects with effectively zero length, allowing you to set up two equations where length equals speed multiplied by time and length equals speed multiplied by 10 minus 100, which solves for both variables. Statements I and II allow you to use the opposite direction crossing formula and the length ratio to solve the system, and II and III provide the relative speed with train B and the distance between poles to solve for the length.

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