What is the correct answer?


A man takes 3 hours 45 minutes to row a boat 15 km downstream of a river and 2hours30minutes to cover a distance of 5km upstream. find the speed of the river current in km/hr.

A. 1km/hr

B. 2km/hr

C. 3km/hr

D. 4km/hr

Correct Answer :

A. 1km/hr

rate downstream=(15/3 ¾)km/hr=(15*4/15)km/hr=4km/hr.

Rate upstream=(5/2 ½)km/hr=(5*2/5)km/hr=2km/hr.

Speed of current=1/2(4-2)km/hr=1km/hr