A boat covers 40 km downstream in 4 hours and the same distance upstream in 8 hours. Find the speed of the stream. MCQ with Answer and Explanation

Explanation:
Speed of train = 150 / 6 = 25 m/s. Total distance to pass platform = 150 + 250 = 400 meters. Time taken = 400 / 25 = 16 seconds.

Explanation:
By 7:00 AM, the first person covers 30 * 2 = 60 km. Relative speed = 40 - 30 = 10 km/h. Time to meet = 60 / 10 = 6 hours. Distance from A = Speed of second person * Time = 40 * 6 = 240 km.

Explanation:
Let each side of square be 2400 km (LCM of 200, 400, 600, 800). Total distance = 4 * 2400 = 9600 km. Total time = 2400/200 + 2400/400 + 2400/600 + 2400/800 = 12 + 6 + 4 + 3 = 25 hours. Average speed = 9600 / 25 = 384 km/h.