Question

The given question consists of a set of statements. Find out whether the data provided in the statements are sufficient to answer the question and mark the option:

What is the length of a running train P crossing another running train Q?

I. These two trains take 12 seconds to cross each other.
II. These trains are running in opposite directions.
III. The length of train Q is 120 metres.

• A. I only
• B. II only
• C. III only
• D. All I, II and III are required
• E. Cannot be determined

Answer 1

The correct option is E

Cannot be determined

Let the length of train P be x metres.

II. These trains are running in opposite directions.

III. Length of train Q is 120 m.

I. Time taken by P to cross Q $=\frac{\left(120+x\right)}{Relativespeed}\Rightarrow 12=\frac{\left(120+x\right)}{Relativespeed}$

Thus, even with statements I, II and III combined, the answer cannot be obtained.