A. 8km/hr
B. 12km/hr
C. 14 km/hr
D. 15 km/hr
E. None of these
Explanation:
Speed downstream = (30 x 2/5)km/hr = 12km/hr
Speed upstream = (30 x 4/15) km/hr = 8 km/hr
Speed of boat in still water = ½ (12 + 8)km/hr = 10 km/hr
Related Mcqs:
- A boat running upstream takes 8 hours 48 min to cover a certain distance while it takes 4 hours to cover the same distance running downstream. What is the ratio between the speed of the boat and the speed of water current respectively?
A. 2 : 1
B. 3 : 1
C. 8 : 3
D. Cannot be determined - A boat running downstream covers 24 km’s in 4 hours while for covering the same distance upstream it takes 6 hours whats the speed of the boat in still water?
A. 3.5km/hr
B. 5.5 km/hr
C. 6 km/hr
D. Data Inadequate
E. None of these - The speed of a boat in upstream is 60 kmph and the speed of the boat downstream is 80 kmph. Find the speed of the boat in still water and the speed of the stream?
A. 70, 10 kmph
B. 35, 27 kmph
C. 50, 60 kmph
D. 45, 55 kmph - 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 - A boat travels upstream from B to A and downstream from A to B in 3 hours. If the speed of the boat in still water is 9km/hr and the speed of the current is 3km/hr, the distance A and B is:_______?
A. 4km
B. 6 km
C. 8 km
D. 12 km - A steamer goes downstream from one port to another in 4 hours, it covers the same distance upstream in 5 hours. If the speed of the stream is 2km/hr,the distance between the two parts is_______?
A. 50km
B. 60km
C. 70km
D. 80 km - The time taken by a man to row his boat upstream is twice the time taken by him to row the same distance downstream. If the speed of the boat in still water is 42 kmph, find the speed of the stream?
A. 12 kmph
B. 13 kmph
C. 14 kmph
D. 15 kmph - If a boat is rowed downstream for 50 km in 5 hours and upstream for 24 km in 6 hours, what is the speed of the boat and the river?
A. (7 , 3) km/hr
B. (6 , 4) km/hr
C. (10 , 4) km/hr
D. None of these - A man covers a distance of 20 km in 3.5 hours partly by running and partly by walking. If he walks at 4 kmph and runs at 10 kmph, find the distance he covers by walking.
A. 10 km
B. 8 km
C. 12 km
D. 9 km - An aeroplane covers a certain distance at a speed of 240 kmph in 5 hours. To cover the same distance in 5/3 hours, it must travel at a speed of:_________?
A. 660 km/hr
B. 680 km/hr
C. 700 km/hr
D. 720 km/hr
