Question

Raj made an upstream journey of 30km in a certain time .If he spend in still water was2kmph less and the speed of the stream was 2kmph more he would have taken ten hours more for that journey.Find his upstream speed (inkmph)​

Answer 1

Step-by-step explanation:

Speed of boat in still water = 30kmph

Speed of boat in still water = 30kmphFormula:

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of stream

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of stream

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/time

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hours

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + a

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - a

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - aBut,

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - aBut,⇒ 60/(30 + a) + 60/(30 - a) = 25/6

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - aBut,⇒ 60/(30 + a) + 60/(30 - a) = 25/6⇒ a = 6 kmph

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - aBut,⇒ 60/(30 + a) + 60/(30 - a) = 25/6⇒ a = 6 kmphSpeed of stream is 6 kmph.

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - aBut,⇒ 60/(30 + a) + 60/(30 - a) = 25/6⇒ a = 6 kmphSpeed of stream is 6 kmph.Downstream speed = 30 + 6 = 36kmph

Speed of boat in still water = 30kmphFormula:Downstream speed = Speed of boat + speed of streamUpstream speed = Speed of boat - Speed of streamSpeed = Distance/timeCalculation:Total time = 4 hours and 10 min = 25/6 hoursLet speed of stream be a kmph.Downstream speed = 30 + aUpstream speed = 30 - aBut,⇒ 60/(30 + a) + 60/(30 - a) = 25/6⇒ a = 6 kmphSpeed of stream is 6 kmph.Downstream speed = 30 + 6 = 36kmph∴ Required time = 136.8/36 = 3.8 hours