Q31. Rajesh rows in still water with a speed of 4.5 kmph to go to a certain place and comes back. Find his average speed for the whole journey, if the river is flowing with a speed of 1.5 kmph?
A. 8 kmph
B. 2 kmph
C. 4 kmph
D. 6 kmph
Q32. A motorboat takes half time to cover a certain distance downstream than upstream. What is the ratio between rate of current and rate of boat in still water?
A. 3 : 2
B. 3 : 1
C. 2 : 3
D. 1 : 3
Q33. If the boat goes 7 kms upstream in 42 min and speed of the stream is 3 kmph, then the speed of the boat in still water?
A. 13 kmph
B. 14 kmph
C. 11 kmph
D. 12 kmph
Q34. A Woman’s downstream swimming rate is thrice of her upstream swimming rate. If she covers 12 km upstream in 2.5 hours, what distance she will cover in 5 hours downstream?
A. 36 km
B. 42 km
C. 72 km
D. 56 km
Q35. Find the speed of stream if a boat covers 36 km in downstream in 6 hours which is 3 hours less in covering the same distance in upstream?
A. 1 kmph
B. 0.5 kmph
C. 1.5 kmph
D. 0.75 kmph
Q36. A man can row upstream at 16 km/hr and downstream at 24 km/hr. Find the speed of the current.
A. 3 kmph
B. 4 kmph
C. 6 kmph
D. 5 kmph
Q37. A person can row 8 1/2 km an hour in still water and he finds that it takes him twice as long to row up as to row down the river. The speed of the stream ?
A. 3.15 kmph
B. 2.35 kmph
C. 2.83 kmph
D. 1.78 kmph
Q38. A motorboat goes 8 km an hour in still water, but takes thrice as much time in going the same distance against the current than going with the current. Then find the speed of the current? A. 6 kmph B. 2 kmph C. 3 kmph D. 4 kmph Q39. A man can row against the current three fourth of a kilometer in 15 min and returns same distance in 10 min, then ratio of his speed to that of current? A. 2:1 B. 5:1 C. 3:1 D. 4:1 Q40. If sum of upstream and downstream speed of a boat is 82 kmph, and the boat travels 105 km. upstream in 3 hr, Find the time taken by boat to cover 126 km downstream. A. 2.6 hrs B. 2.5 hrs C. 2.7 hrs D. 2.8 hrs
