New Enroll in RBI Grade B New Batch - Starts on May 21

    Question

    A cheetah can catch a deer running with a speed of 144

    km/h and is 50 meters ahead of it, in 10 seconds. Find the time taken by the cheetah to catch a zebra that is 170 metres ahead of it and is running with a speed which is 70% of that of the deer.
    A 12 seconds Correct Answer Incorrect Answer
    B 13 seconds Correct Answer Incorrect Answer
    C 10 seconds Correct Answer Incorrect Answer
    D 16 seconds Correct Answer Incorrect Answer
    E None of these Correct Answer Incorrect Answer

    Solution

    Speed of the deer = 144 km/h = 144 × (5/18) = 40 m/s Distance covered by the cheetah in 10 seconds = 50 metres + distance covered by the deer in 10 seconds = 50 + 40 × 10 = 50 + 400 = 450 metres So, speed of the cheetah = 450/10 = 45 m/s Speed of the zebra = 35 × (80/100) = 28 m/s So, relative speed of the cheetah with respect to the zebra = 45 – 28 = 17 m/s Hence, time taken by the cheetah to catch the zebra = 170/17 = 10 seconds

    Practice Next