A boat moves upstream at 8 km/h and downstream at 14 km/h. Find the speed of the river current. MCQ with Answer and Explanation

Explanation:
Time difference = 15 - (-5) = 20 minutes = 20/60 = 1/3 hours. Let distance be d. d/4 - d/6 = 1/3 => d/12 = 1/3 => d = 4 km.

Explanation:
Let total distance be 100 km. First segment = 30 km; Time = 30 / 15 = 2 hours. Second segment = 70 km; Time = 70 / 35 = 2 hours. Total distance = 100 km, Total time = 4 hours. Average speed = 100 / 4 = 25 km/h.

Explanation:
Since time is inversely proportional to speed when distance is constant, the ratio of time taken is the reciprocal of the speed ratio: 1/3 : 1/5 = 5 : 3.