Two bike riders ride in opposite directions around a circular track, starting…

2024

Two bike riders ride in opposite directions around a circular track, starting at the same time from the same point. Biker A rides at a speed of 6 kmph and biker B rides at a speed of 4 kmph. If the track has a diameter of 10 km, after how much time (in hours) will the two bikers meet?

  1. A.

    3.14

  2. B.

    4.12

  3. C.

    7.12

  4. D.

    5.23

Attempted by 4 students.

Show answer & explanation

Correct answer: A

Step-by-Step Solution

To determine the time until the two bikers meet while riding in opposite directions on a circular track, follow these steps:

  1. Calculate the total distance (Circumference of the track):

    • The formula for circumference (C) is C = pi * D, where D is the diameter.

    • Given diameter D = 10 km.

    • Circumference = 10 * pi km.

  2. Determine the relative speed:

    • Since the bikers are moving in opposite directions, their relative speed is the sum of their individual speeds.

    • Relative speed = 6 kmph + 4 kmph = 10 kmph.

  3. Calculate the time until they meet:

    • Time = Distance / Relative speed

    • Time = (10 * pi km) / (10 kmph)

    • Time = pi hours.

    • Taking pi approximately 3.14, the time is 3.14 hours.

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