[SBI (Management Executive) 2014] What is the length of the train? I. The train crosses a signal post in 9 s. II. If the train with speed x km/h crosses another train 100 m long coming from the opposite direction at 60 km/h in 15 s.
A) If the data in statement I alone are sufficient to answer the question, while the data in statement II alone are not sufficient to answer the question
B) If the data in statement II alone are sufficient to answer the question, while the data in statement I alone are not sufficient to answer the question
C) If the data either in statement I alone or in statement II alone are sufficient to answer the question
D) If the data given in both the statements I and II together are not sufficient to answer the question
E) If the data in both the statements I and II together are necessary to answer the question
Correct Answer: E
$ \Rightarrow $ $ ( \frac{5y}{162}+60 )\times \frac{15}{36}=\frac{y+100}{10} $ (i) It is to be noted that when a train crosses a pole, in distance covered = length of the train. When it crosses another train, Relative speed $ \times $ time = Sum of lengths of both trains Hence, from statements I and II, we can determines length of the train.