A train 150 meters long completely passes a station pole sign in 6 seconds flat. Find its speed in km/h. MCQ with Answer and Explanation

Explanation:
Let original speed be s. 450/s - 450/(s+5) = 1 => 450(s + 5 - s) = s(s + 5) => 2250 = s(s + 5). Solving s^2 + 5s - 2250 = 0 gives (s - 45)(s + 50) = 0. Since speed is positive, s = 45 km/h.

Explanation:
Relative speed = 8 - 5 = 3 m/s. Time to meet for the first time = Circumference / Relative speed = 400 / 3 = 133.33 seconds.

Explanation:
Speed in m/s = 200 / 24 = 25/3 m/s. To convert to km/h, multiply by 18/5. Speed = (25/3) * (18/5) = 5 * 6 = 30 km/h.