# Quants Questions : Time and Distance Set 8 – Boats

Hello Aspirants. Welcome to Online Quantitative Aptitude Section in AffairsCloud.com. Here we are creating question sample in Time and Distance- Boats and streams with Explanation, which is common for all the IBPS,SBI,SSC and other competitive exams. We have included Some questions that are repeatedly asked in bank exams !!!

1. A boat can travel 4.2km upstream in 14min. If the ratio of the speed of the boat in still water to the speed of the stream is 7:1. How much time will the boat take to cover 17.6km downstream ?
A)56min
B)44min
C)32min
D)48min
E)None of these
B)44min
Explanation :
Speed = 7x:x
Downstream = 8x; upstream = 6x
Upstream speed = 4.2*60/14 = 18kmph
6x = 18
X = 3
Downstream = 8*3 = 24
Time taken for 17.6km = 17.6*60/24 = 44min

2.  A man can row at 4 kmph in still water. If the velocity of the current is 1 kmph and it takes him 1 hour to row to a place and come back. how far is that place.
A)1.8km
B)2.6km
C)1.5km
D)3.2km
E)None of these
A)1.8km
Explanation :
Let the distance is x km
Rate downstream = 4 + 1 = 5 kmph
Rate upstream = 4 – 1 = 3 kmph
then
x/5 + x/3 = 1
3x + 5x = 15
x = 15/8 = 1.8 km

3. Arun  takes thrice 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 stream is
A)3:1
B)1:2
C)2:1
D)2:3
E)None of these
C)2:1
Explanation :
speed downstream = x kmph
Speed upstream = 3x kmph
(3x+x)/2 : (3x-x)/2
4x/2 : 2x/2 = 2:1

4. A boat takes 30 hours for travelling downstream from point A to point B and coming back to point C midway between A and B. If the velocity of the stream is 2 kmph and the speed of the boat in still water is 15 kmph, what is the distance between A and B?
A)342km
B)356km
C)316km
D)308km
E)None of these
D)308km
Explanation :
velocity of the stream = 2 kmph
Speed of the boat in still water is 15 kmph
Speed downstream = (15+2) = 17 kmph
Speed upstream = (15-2) = 13 kmph
Let the distance between A and B be x km
x/17+(x/2)/13=30
x/17+x/26=30
43x/442=30
x=30*442/43 = 308.37 = 308km
distance between A and B = 308 km

5. A boat takes 120min less to travel 30km downstream than to travel the same distance upstream.If the speed of the boat in still water is 8kmph then the speed of the stream is
A)2kmph
B)8kmph
C)3kmph
D)4kmph
E)None of these
A)2kmph
Explanation :
Speed of the stream = x
(30/8-x) – (30/8+x)= 120/60 = 2/1
30(8+x) – 30(8-x) = 2[64 – x2]
240+30x-240x+30x = 2[64 – x2]
60x = 128- 2x2
2x2+60x-128 = 0
x2+30x-64 = 0
(x+32)(x-2) = 0
X=2kmph

6. A boat running downstream covers a distance of 24km in 4hrs, while for covering
the same distance upstream it takes 6hrs, what is the speed of the boat in still water ?
A)12kmph
B)10kmph
C)5kmph
D)7kmph
E)None of these
C)5kmph
Explanation :
24/x-y = 6
6x – 6y = 24………….(1)
24/x+y = 4
4x+4y = 24………….(2)
24x – 24y = 96
24x+24y = 144
Solve abv 2 equ
48x = 240
X = 240/48 = 5

7. A man swims downstream 40 km in 5 hours and upstream 24 km in 2 hours. Find his speed in still water ?
A)10kmph
B)15kmph
C)8kmph
D)12kmph
E)None of these
A)10kmph
Explanation :
Downstream  = 40/5= 8 kmph
Upstream = 24/2== 12 kmph
Speed in still water = 1/2 ( 8+12) = 10 kmph

8. The speed of a boat in still water in 12 km/hr and the rate of current is 4 km/hr. The
distance travelled downstream in 12 minutes is
A)3.2km
B)4.7km
C)5.1km
D)2.7km
E)None of these
A)3.2km
Explanation :
Speed downstream = (12 + 4) kmph = 16 kmph.
Distance travelled = 16 x12/60 km = 3.2 km

9. 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)1.30hrs
B)3.209hrs
C)2.15hrs
D)1.25hrs
E)None of these
D)1.25hrs
Explanation :
downstream =(1x 60)/10  = 6 kmph
Rate upstream = 2 km/hr.
Speed in still water =(6 + 2) /2= 4 kmph
time = 5/4 =  1.25hrs

10. A boat goes 24 km upstream and 28 km downstream in 6 hours. It goes 30km upstream and 21 km downstream in 6 hours and 30 minutes. The speed of the boat in still water is
A)10kmph
B)4kmph
C)6kmph
D)8kmph
E)None of these
A)10kmph
Explanation :
speed of the boat in still water = x kmph
speed of the current = y kmph
upstream speed = (x – y) kmph
downstream speed = (x + y)kmph
24/(x-y) + 28/(x+y) = 6
30/(x-y) + 21(x+y) = 13/2
X = 10kmph

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