A person can row 12 km/h in still water. If the speed of the river current is 4 km/h, find the time taken to row 32 km upstream. MCQ with Answer and Explanation

Explanation:
Circumference of the wheel = 2 * (22/7) * 7 = 44 cm = 0.44 meters. Total distance = 44 meters. Number of revolutions = 44 / 0.44 = 100.

Explanation:
Time = 4 hours 40 minutes = 4 + 40/60 = 4.666 hours = 14/3 hours. Speed = Distance / Time = 280 / (14/3) = 280 * 3 / 14 = 20 * 3 = 60 km/h.

Explanation:
New speed = 7/9 of usual speed => New time = 9/7 of usual time. Difference = 2/7 of usual time = 12 minutes. 1/7 of usual time = 6 minutes => Usual time = 42 minutes.