As man is not travelling against anything, hence why is rate of current subtracted from 15 in first step? I think the first step should be final step.
Tushar said:
(Sun, Dec 5, 2010 03:05:41 PM)
No, Man is travelling with water when it is 15 km, so if we subtract 2.5, it gives us man's own speed and then again subtracting gives us upstream speed
Pinky said:
(Thu, Feb 24, 2011 09:43:55 AM)
Please explain me, why man's rate subtract form the current,
I'm not understanding.
Ashwini said:
(Sun, Feb 27, 2011 01:29:31 PM)
I'm not understanding
Balaji said:
(Fri, Mar 18, 2011 12:49:40 AM)
Let me explain:
First of all the problem has the data,
speed of man is with current i.e., 15km/hr.
here we can compare it with down stream i.e., speed of boat with the stream.
if we want to take man's speed only we got to substract the speed of current i.e., 2.5 km/hr.
therefore, 15-2.5 = 12.5 km/hr, which is actually man's speed.
In the question they asked us to determine the speed of the man against the current. Here we will compare it with up stream.
i.e. speed of boat against the stream.
there fore, speed of man - speed of current
=12.5-2.5=10km/hr
Khaleel said:
(Tue, Mar 29, 2011 11:11:09 PM)
You are right samarth.
Geetha said:
(Thu, Jun 16, 2011 03:35:16 PM)
Thank you. Now I understand clearly.
Sravya said:
(Sat, Sep 3, 2011 08:15:24 PM)
Let speed of man be 'a'
speed of current be 'b'
given man's speed with current (a+b)=15 km\hr nd speed of current is 2.5
substitute in abv eqn (a+2.5)=15
a=15-2.5
a=12.5
but problem is abt finding man's speed against current i,e
(a-b)=12.5-2.5
=10
Anup Gupta said:
(Fri, Sep 23, 2011 03:51:27 PM)
No upstream speed can be any one less than 12.5. I. E. Against the stream. Question is not that what will be the speed if he will move against the stream at 2.5.
Hitesh Bulani said:
(Wed, Dec 7, 2011 10:56:53 PM)
Thanku balaji.
Mani said:
(Thu, Jan 5, 2012 09:26:42 PM)
Here they did not mention that is/clearly not questioned that this is a boad and stream problem.
