Excluding stoppages, a truck travels at 90 km/h and including stoppages it travels at 75 km/h. How many minutes does the truck stop per hour? MCQ with Answer and Explanation

Explanation:
Downstream speed = 16 / 2 = 8 km/h. Upstream speed = 16 / 4 = 4 km/h. Speed in still water = (8 + 4) / 2 = 6 km/h.

Explanation:
Downstream speed = 24 / 2 = 12 km/h. Upstream speed = 24 / 6 = 4 km/h. Speed of stream = (12 - 4) / 2 = 8 / 2 = 4 km/h.

Explanation:
Speed of train = 54 * (5/18) = 15 m/s. Length of train = Speed * Time to cross observer = 15 * 8 = 120 meters. Total distance to cross platform = Speed * Time = 15 * 20 = 300 meters. Platform length = 300 - 120 = 180 meters.