Quantitative Aptitude Ques 694

Question: Directions: Each of the questions below consists of a question and three statements I, II and III given below it. You have to decide whether the data provided in the statements are sufficient to answer the question. [IBPS (PO) 2012]

What is the speed of train? I. The train crosses a signal post in 20 s. II. The train crosses a 260 m long platform in 33 s. III. The train crosses another stationary train of same length in 40 s

Options:

A) I and III

B) II and either I or III

C) All I, II and III

D) Any two of the three

E) Even with all three statements answer cannot be given

Show Answer

Answer:

Correct Answer: B

Solution:

  • Let the length of train be x m and Its speed be y m/s. I. $ \frac{x}{y}=20 $ … (i)
    II. $ \frac{x+260}{y}=33 $ … (ii) III. $ \frac{2x}{y}=40 $ … (iii) Clearly, II and either I or III are necessary to answer the question.