Aptitude - Boats & Streams Online Quiz



Following quiz provides Multiple Choice Questions (MCQs) related to Boats & Streams. You will have to read all the given answers and click over the correct answer. If you are not sure about the answer then you can check the answer using Show Answer button. You can use Next Quiz button to check new set of questions in the quiz.

Questions and Answers

Q 1 - A man can push 6 km/hr in still water. It takes him twice as long to line up as to column down the river. Find the rate of the stream.

A - 1.2 km/hr

B - 1 km/hr

C - 2 km/hr

D - 1.5 km/hr

Answer : C

Explanation

Let men's rate upstream be x km/hr`At that point, men's rate downstream = 1/2 (2x+x) km/hr = 3x/2 km/hr`And there 4; 3x/2 =6 <=> x= (2*6)/3 =4.`And there 4: 4 km/hr, rate downstream = (2*4) km/hr = 8 km/hr`Rate of stream = 1/2 (8-4) km/hr = 2 km/hr

Q 2 - In a stream running at 2 km/hr, a speedboat goes 10km upstream and back again to the beginning stage in 55 min. discover the velocity the speedboat in still water.

A - 18 km/hr

B - 20 km/hr

C - 22 km/hr

D - 10 km/hr

Answer : C

Explanation

Let the pace of the speedboat in still water be x km/hr.`Speed downstream =(x+2) km/hr, speed upstream =(x-2) km/hr.`∴ 10/(x-2) +10/(x+2) =55/60=>1/(x-2) +1/(x+2) =55/600=11/120`=> (x+2) +(x-2)/(x-4) =11/120=>11(x2-4) =240x`=>11x2-240x-44=0`=>11x2-242x+2x-44=0`=> 11x(x-22) +2(x-22) =0`=>(x-22) (11x+2) =0=> x=22.`Velocity of speedboat in still water=22km/hr.

Q 3 - A boat is paddled downstream at 15.5km/hr and upstream at 8.5km/hr. The rate of the stream is:

A - 3.5 km/hr

B - 5.75 km/hr

C - 6.5 km/hr

D - 7 km/hr

Answer : A

Explanation

Speed downstream =15.5km/hr, Speed upstream =8.5km/hr.`Speed of the stream=1/2(15.5-8.5) km/hr=3.5 km/hr

Q 4 - A watercraft covers a separation of 30km in 5/2 hrs running downstream. While returning, it covers the same separation 15/4hrs .What is the velocity of the watercraft in still water?

A - 8 km/hr

B - 12 km/hr

C - 14 km/hr

D - 10 km/hr.

Answer : D

Explanation

Speed downstream = (30*2/5) km/hr=12km/hr.`Speed upstream= (30*4/15) km/hr=8 km/hr.`Speed of boat in still water=1/2(12+8) km/hr=10 km/hr.

Q 5 - A boat can push 1 km with stream in 10 minutes and 1 km against stream in 20 minutes. What is the rate of the vessel in still Water?

A - 1.5 km/hr

B - 3 km/hr

C - 3.4 km/hr

D - 4.5 km/hr.

Answer : D

Explanation

Distance moved downstream in 10 min=1km.`Distance moved downstream in 60 min= (1/10*60) km=6 km.`Distance moved upstream in 20 min =1 km.`Distance moved upstream in 60 min = (1/20*60) km = 3 km.`Speed downstream =6 km/hr, Speed upstream =3 km/hr`Speed of the boat in still water =1/2(6+3) km/hr =4.5 km/hr.

Q 6 - A boat running upstream takes 8 hours 48min to cover a certain separation, while it takes 4 hour to cover the same separation running downstream. What is the proportion between the velocity of the vessel and the velocity of water flow respectively?

A - 2:1

B - 3:1

C - 8:3

D - None of these

Answer : C

Explanation

Let the speed of boat be x km /hr and speed of stream be y km/hr.`44/5 * (x-y) = 4 * (x+y) => 44(x-y) =20 (x+y) => 11 (x-y) = 5(x+y) => 6x=16y`=> x/y= 16/6 = 8/3 => x: y = 8:3.

Q 7 - A vessel goes 6 km in an hour in still water. It requires thrice as much investment in covering the same separation against the current. Velocity of the current is:

A - 2 km/hr

B - 3 km/hr

C - 4 km/hr

D - 5 km/hr.

Answer : C

Explanation

Speed in still water =6 km/hr.`Speed against the current =6/3 km/hr =2 km/hr`Let the speed of the current be x km/hr`6-x = 2 => x = 4 km/hr.

Q 8 - Aman can push 15/2 kms an hour in still water and he finds that it takes him twice as long to down the stream. The rate of the stream is:

A - 2.4 km/hr

B - 2.5 km/hr

C - 3.4 km/hr

D - 3.5 km/hr

Answer : B

Explanation

Let the rate of stream be x km/hr. Then,`Speed downstream = (15/2 +x) km/hr, Speed upstream = (15/2 - x) km/hr`(15/2 +x) = 2 (15/2 -x) => 3x =15/2 => x = 15/2*3 = 5/2 = 2.5`∴ Rate of stream=2.5 km/hr

Q 9 - A boatman goes 2km against the current of stream in 40 min. what's more, comes back to the same spot in 30 min. What is his rate of paddling in still water?

A - 5 km/hr

B - 6 km/hr

C - 7 km/hr

D - 8 km/hr

Answer : C

Explanation

Distance covered upstream in 40min = 4 km.`Distance covered upstream in 60 min = (4/40*60) km= 6 km`Distance covered downstream a in 30 min = 4 km`Distance covered downstream in 60 min = (4/30 * 60) km = 8 km.`Speed upstream =3 km/hr, speed downstream =4 km/hr.`Speed in still water = 1/2 (6 +8) km/hr=7 km /hr.

Q 10 - A boat sets aside half time in moving a sure separation downstream then upstream. What is the proportion between rate in still Water and rate of current and flow?

A - 1:2

B - 3:1

C - 2:1

D - 1:3

Answer : B

Explanation

Let the speed of boat in still water be u km/hr and speed of the current be v km/hr.`Rate downstream = (u+v) km/hr, Rate upstream= (u-v) km/hr.`Let the distance covered in each case be x km. Then,`2x/(u+v) = x/ (u-v) => 2 (u-v) = (u+v) => u =3v =>u/v=3/1`Required ratio = 3:1.

aptitude_boats_streams.htm
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