WBCS.LIVE practice question

A train travels a distance of 300 Km. at a constant speed. If the speed of the train is increased by 5 Km. an hour, the journey would have taken 2 hours less. The speed of the train will be

Solve this multiple-choice question and check the correct answer with its explanation below.

Answer options

  1. 30 Km./h
  2. 25 Km./h
  3. 20 Km./h
  4. 35 Km./h

Correct answer and explanation

Correct answer: 25 Km./h

Explanation: āœ… Correct Answer: B. 25 Km./h šŸ“š Explanation: Let the original speed be v. The equation is 300/v - 300/(v + 5) = 2. This simplifies to 1500 / (v squared + 5v) = 2, which means v squared + 5v - 750 = 0. Solving this quadratic results in v = 25 as the positive speed. Therefore, the original speed of the train was exactly 25 kilometers per hour.