Problems on Boats Stream

Q11. A boat goes 9 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) 6 km/hr
(b) 8 km/hr
(c) 9 km/hr
(d) 10 km/hr

Q12. A man rows 40 km downstream and 22 km upstream taking 5 hours each time. What is the velocity of the current ?
(a) 1.8 km/h
(b) 1.9 km/h
(c) 2.3 km/h
(d) 2.7 km/h

Q13. A man rows 42 km down stream in 7 hours and 15 km upstream in 5 hours. What is the velocity of the current ?
(a) 1.3 km/h
(b) 1.5 km/h
(c) 2.2 km/h
(d) 2.5 km/h

Q14. A man can row 8 km/h in still water. When the river is running at 2 km/h, it takes him 4 hours to row to a place and back. How far is the place ?
(a) 9 km
(b) 11 km
(c) 12 km
(d) 15 km

Q15. A boat is rowed downstream at 15.5 km/h and upstream at 8 km/h. The speed of the stream is
(a) 2.19 km/h
(b) 3.75 km/h
(c) 4.12 km/h
(d) 4.33 km/h

Q16. The speed of a motor boat is that of the current of water as 36:4. The boat goes along with the current in 4 hours 30 minutes. It will come back in
(a) 3(5/7) hr
(b) 3(1/5) hr
(c) 4(5/7) hr
(d) 5(5/8) hr

Q17. A man can row upstream at 5 km/hr and downstream at 10 km/hr. Find the man's rate in still water.
(a) 5.5 km/h
(b) 6.5 km/h
(c) 7.5 km/h
(d) 8.5 km/h

Q18. A boat takes one fourth time in moving a certain distance downstream than upstream. What is the ratio between rate in still water and rate of current ?
(a) 3 : 7
(b) 4 : 5
(c) 5 : 3
(d) 6 : 5

Q19. A man can row 6½ kms an hour in still water and he finds that it takes him twice as long to row down the river. The rate of the stream is
(a) 2(1/6) km/h
(b) 3(1/5) km/h
(c) 3(1/7) km/h
(d) 4(1/5) km/h

Q20. A boat covers a distance of 30 km in 2½ hrs running downstream. While returning it covers the same distance in 3¾ hrs. What is the speed of the boat in still water.
(a) 6 km/h
(b) 7 km/h
(c) 8 km/h
(d) 10 km/h

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