The speed of a boat downstream is 18 km/h and upstream is 12 km/h. How much distance can the boat cover in still water in 3 hours? MCQ with Answer and Explanation

Explanation:
Time difference = 15 - 5 = 10 minutes = 10/60 = 1/6 hour. Let distance be d. d / 3 - d / 4 = 1/6 => d / 12 = 1/6 => d = 2 km.

Explanation:
Time = 30 minutes = 0.5 hours. Distance covered by A = 60 * 0.5 = 30 km. Distance covered by B = 80 * 0.5 = 40 km. Distance between them = sqrt(30^2 + 40^2) = sqrt(900 + 1600) = sqrt(2500) = 50 km.

Explanation:
Total distance = 180 + 220 = 400 meters. Speed = 400 / 16 = 25 m/s. In km/h = 25 * (18/5) = 90 km/h.