Discuss Forum

1.

A man takes 3 hours 45 minutes to row a boat 22.5 km downstream of a river and 2 hours 30 minutes to cover a distance of 10 km up stream . Find the speed of the river current in km /hr.

  • A. 1 km/hr
  • B. 1 km/hr
  • C. 1 km/hr
  • D. 1 km/hr

Answer: Option A

Explanation:

Speed of the boat = x kmph, the river current = y mph.
3H45M = (3 + 45/60) hr = 15/4 hr
2H30M = (2 + 30/60) hr = 5/2 hr.
According to the question:
x + y = 22.5/(15/4) = 6
x - y = 10/(5/2) = 4
2x = 2
x = 1.
Ans: A

 


Post your comments here:

Name:
Mobile:
Email:(Optional)

» Your comments will be displayed only after manual approval.