Aptitude - Boats and Streams - Discussion
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Read more:"Nothing is impossible to a willing heart."
- (Proverb)
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The speed of a boat in still water in 15 km/hr and the rate of current is 3 km/hr. The distance travelled downstream in 12 minutes is:
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1.2 km | [B]. |
1.8 km | | [C]. |
2.4 km | [D]. |
3.6 km |
Answer: Option A
Explanation:
Speed downstream = (15 + 3) kmph = 18 kmph.
| Distance travelled = |
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18 x |
12 |
 km = 3.6 km. |
| 60 |
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Kanchan Tarwani said:
(Thu, Jul 1, 2010 11:45:59 AM)
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| why we add current rate with speed of still water?? |
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Brajendra said:
(Mon, Jul 12, 2010 09:45:35 PM)
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why we add current rate with speed of still water??it has to
substract |
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Nagarjun said:
(Tue, Jan 11, 2011 12:07:11 AM)
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| They have specified as downstream so we have to add. |
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Sanjana said:
(Fri, Jul 15, 2011 06:22:21 AM)
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| Why we add current rate with speed? |
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Bindu said:
(Sun, Sep 11, 2011 08:13:56 AM)
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Rate of current=1/2(downstream speed- upstream speed)
ie=1/2[(U+V)-(U-V)]
=1/2(U+V-U+V)
=2V/2
=V
SO RATE OF CURRENT = V(SPEED OF STREAM) |
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Angu said:
(Tue, Nov 29, 2011 04:39:14 PM)
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| Thanks bindu |
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Gautam said:
(Wed, Dec 28, 2011 10:53:54 PM)
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Use the formula= if the speed of a boat in still water is U km/hr and the speed of the stream is V km/hr, then
speed down stream = (u+v)km/hr
(15+3)km/hr = 18 km/hr
Distance travelled = (18 x 12/60)=3.6km ANSWER
[60 is here because 1 minute=60seconds] |
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