A. 40 Minutes
B. 1 Hour
C. 1 hr 15 Min
D. 1 Hr 30 Min
Explanation:
Speed upstream = 2km/hr.
Speed downstream = 6 km/hr
Speed in stationary water = ½ (6 + 2) km/hr = 4 km/hr
Time is taken to cover 5 km in stationary water
= (1/4 x 5) 1 hr 15 min
Related Mcqs:
- A boatman goes 2 km against the current of the stream in 1 hour and goes 1 km along the current in 10 minutes. How long will it take to go 5 km in stationary water?
A. 40 minutes
B. 1 hour
C. 1 hr 15 min
D. 1 hr 30 min - A man can row three-quarters of a kilometre against the stream in 11 minutes and down the stream in 7 minutes. The speed (in km/hr) of the man in still water is:_________?
A. 2
B. 3
C. 4
D. 5 - A man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. The ratio of the speed of the boat (in still water) and the stream is________?
A. 2 : 1
B. 3 : 1
C. 3 : 2
D. 4 : 3 - Two pipes can fill a tank in 18 minutes and 15 minutes. An outlet pipe can empty the tank in 45 minutes. If all the pipes are opened when the tank is empty, then how many minutes will it take to fill the tank?
A. 12
B. 13
C. 11
D. 10 - Pipe A can fill a tank in 16 minutes and pipe B cam empty it in 24 minutes. If both the pipes are opened together after how many minutes should pipe B be closed, so that the tank is filled in 30 minutes?
A. 20
B. 24
C. 23
D. None of these - Three pipes A, B and C can fill a tank from empty to full in 30 minutes, 20 minutes and 10 minutes respectively. When the tank is empty, all the three pipes are opened. A, B and C discharge chemical solutions P, Q and R respectively. What is the proportion of solution R in the liquid in the tank after 3 minutes?
A. 5/11
B. 6/11
C. 7/11
D. 8/11 - A man can row three-quarters of a kilometer against the stream in 11 ¼ minutes and return in 7 ½ minutes. The speed of the man in still water is________?
A. 2km/hr
B. 3km/hr
C. 4 km/hr
D. 5 km/hr - A boat goes 6 km in an hour in still water. It takes thrice as much time in covering the same distance against the current. Speed of the current is_______?
A. 2 km/hr
B. 3km/hr
C. 4km/hr
D. 5 km/hr - A boat is rowed downstream at 15.5km/hr and upstream at 8.5 km/hr. The speed of the stream is________?
A. 3.5km/hr
B. 5.75km/hr
C. 6.5km/hr
D. 7km/hr - A boat goes 24 km downstream in 10 hours, it takes 2 hours more to cover the same distance against the stream. What is the speed of the boat in still water?
A. 2km/hr
B. 2.8 km/hr
C. 4 km/hr
D. 4.2 km/hr
E. None of these
