A car covers a certain distance at 45 km/h. If it increases its speed to 60 km/h, it arrives 30 minutes earlier. Find the total distance. MCQ with Answer and Explanation

Explanation:
New Speed = 0.8 * Usual Speed. Since distance is constant, New Time = Usual Time / 0.8 = 1.25 * Usual Time. Increase in time = 0.25 * Usual Time = 15 minutes. Usual Time = 15 / 0.25 = 60 minutes.

Explanation:
When equal distances are traveled at speeds v1 and v2, the average speed is the harmonic mean: 2v1*v2 / (v1 + v2).

Explanation:
Downstream speed = 15 + 3 = 18 km/h. Time = 20 minutes = 20/60 = 1/3 hour. Distance covered = Speed * Time = 18 * (1/3) = 6 km.