# 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.

Q 1 - A man can push upstream at 6km/hr and downstream at 10 km/hr. Discover man's rate in still water and the rate of the momentum.

### Answer : C

### Explanation

Speed upstream =6 km/hr`Speed downstream = 10 km/hr`Rate in still water = 1/2 (10-6) km/hr. = 6km/hr`Rate of the current = 1/2 (10+6) km/hr =8 km/hr

Q 2 - A man can push 30km upstream and 44km downstream in 10 hours. Additionally, he can push 40km upstream and 55km downstream in 13 hours. Discover the rate of flow and the current of the man in still water.

### Answer : C

### Explanation

Let speed upstream be x km/hr and the velocity downstream be y km/hr`At that point, 30/x+44/y=10 ... (i) and 40/x+55/y=13 ... (ii)`Increasing (ii) by 4, (i) by 5 and subtracting, we get: 10/x=2=>x=5.`Putting x=5in (i) we get 4y=44=> y=11.`∴ Speed upstream =5km/hr, speed downstream=11km/hr.`Velocity of the current =1/2(11-5) km/hr=3km/hr.`Velocity of man in still water =1/2(11+5) km/hr=8km.

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

### 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 boat running downstream covers a separation of 10km in 2 hours .While returning upstream the boat takes 5 hours to cover the same separation. In the event that the velocity of the current and flow is 1.5 kmph, what is the speed of the boat in still water?

### Answer : B

### Explanation

Speed downstream =10/2 km/hr=5 km/hr.`Speed upstream =10/5 km/hr = 2 km/hr.`Speed of boat in still water = 1/2 (5+2)km/hr=3.5km/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?

### 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 - Aman can push at 5 km/hr in still Water. It the stream is running at 1km/hr, it takes him 75 min. to line to a spot and back. How far is the spot?

### Answer : B

### Explanation

Speed downstream = (5+1) km/hr=6 km/hr`Speed upstream = (5-1) km/hr=4 km/hr.`Let the required distance be x km. Then,`x/6+ x/4=75/60 = 5/4 => (2x+3x) =15 => 5x = 15 => x=3.`Required distance =3km.

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:

### 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:

### 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?

### 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 - Aman lines to a spot 48 km far off and in 14 hours. He finds that he can push 4km with the stream in the same time as 3km against the stream. The rate of the stream is:

### Answer : B

### Explanation

Suppose he moves 4 km downstream in x hrs.`Then, speed downstream = 4/x km/hr, speed upstream =3/x km/hr`∴ 48/ (4/x) + 48 / (3/x) = 14 => 12x + 16x =14 => 28x = 14`=> x= 1/2.`Speed downstream = 4 / (1/2) km/hr=8 km/hr.`Speed upstream= 3/(1/2) km/hr =6km/hr.`Rate of stream = 1/2(8 - 6) km /hr=1 km/hr.