Latest IBM Aptitude Question SOLUTION: A boat goes 8 km upstream in 24 minutes. The speed of stream is 4 km/hr. The speed of boat in still water is: A. 25 km/hr B. 26 km/hr C. 22 km/hr D. 24 km/hr

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(#M40128175) IBM Numerical Ability question Keep an EYE

A boat goes 8 km upstream in 24 minutes. The speed of stream is 4 km/hr. The speed of boat in still water is:

A. 25 km/hr

B. 26 km/hr

C. 22 km/hr

D. 24 km/hr

Asked In IBM naga kusuma (9 years ago)

Unsolved Read Solution (12)

Is this Puzzle helpful?   (39)   (13) Submit Your Solution Time Distance and Speed

Read Solution (12) :

Shaik Habimunnisa  (9 years ago)

each machine got 2hrs to complete work,so for 100% actual speed time is 2 hrs then..taking 25% in that the work complete for half an hour...so,there are two machines so one hour....(reduced)...then the ans will be
9 hrs

Is this solution Helpfull? Yes (27) | No (8)  

k.shiva kumari  (8 years ago)

rate upstream =8/24*60=20kmph
speed of stream=4kmph
let speed of boat in still water=xkmph
speed upstream=x-4kmph
x-4=20
x=24kmph

Is this solution Helpfull? Yes (25) | No   

prabhat kumar  (9 years ago)

2 of m/c speed increased 25% so now it is 2.50
tot=3+2.50=5.50
let x hour will take to complete the work
5*10=5.50*x
x=9 1/11 will take to complete the same work

Is this solution Helpfull? Yes (13) | No (8)  

supratip bhattacharya  (9 years ago)

speed increased by 25% means time decreased by 20%
Each machine take 2 hrs. so 2 machines time decreased by=3.2 hr rest of the three take 6 hr
Total time=3*2+2*(2*80/100)=9.2

Is this solution Helpfull? Yes (8) | No (9)  

praveen  (8 years ago)

boatstream=?,,, currentstream=4km/hr
upstream=boatstream-currentstream
upstream=distance/time=(8*60)/24=20km/hr
20=boatstream-4
boatstream=20+4=24

Is this solution Helpfull? Yes (6) | No   

thenmozhi  (9 years ago)

what is the correct answer?

Is this solution Helpfull? Yes (4) | No   

RUDRADIP DEY  (9 years ago)

each ordinary machine takes 2 hours.
ratio of time consumption between single ordinary machine and single improvised machine
125:100 = 2:x
so now one improved machine will take 1.6 hours instead of 2 hours. 2 machine will take 3.2 hours.
total time consumption is (3*2)+3.2= 9.2 hours.

Is this solution Helpfull? Yes (1) | No (3)  

ranjan  (7 years ago)

33. A boat goes 8 km upstream in 24 minutes. The speed of stream is 4 km/hr. The speed of boat in still water is:
A. 25 km/hr B. 26 km/hr
C. 22 km/hr D. 24 km/hr
Hide Answer|Notebook | Discuss
answer with explanation
Answer: Option D

Explanation:

Speed upstream @@=dfrac{8}{left(dfrac{24}{60}right)}@@ = 20 km/hr

Speed of the stream = 4 km/hr

speed of boat in still water = (20+4) = 24 km/hr

Is this solution Helpfull? Yes (1) | No   

Manish  (6 years ago)

Su=x-y,where x is the speed of boat in still water, y is the speed of stream and Su is boat upstream speed so,
Su=8/24/60=20km/hr
Now,
20=x-4
X=24km/hr

Is this solution Helpfull? Yes (1) | No   

charan  (9 years ago)

9.2 hours

Is this solution Helpfull? Yes | No (4)  

Gaddameedi shireesha  (9 years ago)

I think 9 z correct ans

Is this solution Helpfull? Yes | No (3)  

Nitesh Thakur  (5 years ago)

D = 8km
T = 24min (i.e) 24/60hr
speed in upstream is " a-b=speed "
where a is the speed of the boat and b is the speed of the stream
so we have the value of b i.e speed of the stream
and we have the value of distance and time of the boat, we can find the speed i.e a-b = speed
by substitute the value of b and speed we get the value of a which was the speed of the boat in the still water.
hence we get the above equation as :
a-b=speed
a-4=20 // speed = distance/time 8*60/24=20
a=24
hence the speed of the boat is 24km/hr.

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