Question

    Two cars start from a place with a speed of 75 km/hr at

    an interval of 17 minutes. What is the speed of a man coming from the opposite direction towards the place if he meets the cars at an interval of 15 minutes?
    A 20 km/hr Correct Answer Incorrect Answer
    B 15 km/hr Correct Answer Incorrect Answer
    C 10 km/hr Correct Answer Incorrect Answer
    D 5 km/hr Correct Answer Incorrect Answer
    E 25 km/hr Correct Answer Incorrect Answer

    Solution

    Distance covered in 17 minutes at 75 km/hr =75 x (17/60) Distance covered in 15 minutes at (75 + x) km/hr = (15/60) x (75 + x) Now, Distance covered in 17 minutes at 75 km/hr = Distance covered in 15 minutes at (75 + x) km/hr ⇒ 75 x (17/60) = (15/60) x (75 + x) ⇒ 75 x 17 = 1125 + 15x ⇒ 1275 = 1125 + 15x ⇒ 15x = 1275 - 1125 = 150 ⇒ x = 10 km/hr

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