A vehicle covers a path of 360 km at a certain speed. If the speed is increased by 10 km/h, the trip takes exactly 3 hours less. Find the original speed of the vehicle. MCQ with Answer and Explanation

Let original speed be s. 360/s - 360/(s+10) = 3 => 120/s - 120/(s+10) = 1 => 120(10) = s(s+10) => 1200 = s(s+10). Solving s^2 + 10s - 1200 = 0 gives (s - 30)(s + 40) = 0. Since speed is positive, s = 30 km/h.