### Discussion :: Boats and Streams - General Questions (Q.No.1)

Balaji said: (Mar 18, 2011) | |

In the question they given the data that speed of boat 13 km/hr and speed of stream is 4 km/hr and they asked us to solve the time taken by the boat in down stream for a distance of 68 kms. we know as per the formula down stream means speed of boat + speed of stream therefore, down stream = 13+4=17 km/hr as per the problem we got to find time taken by boat to travel a distance of 68km down stream. we have formula that, time=distance/speed =68/17 =4 hours |

Manasa said: (Jun 12, 2011) | |

Thanks Balaji. |

Geetha said: (Jun 16, 2011) | |

Thanks for your explanation. |

Anshu said: (Apr 4, 2012) | |

Total speed during downstream, Speed = 13kmph + 4 kmph = 17 kmph. Time = distance / speed = 4 hours. Hope this helps! |

Arun.D said: (Jun 3, 2013) | |

Speed of boat in still water = 13km/hr. Speed of the stream = 4km/hr. Time taken by the boat to go 68 km downstream = ? Speed of boat in downstream = (13+4)km/hr. = 17km/hr. Time = distance/speed. = 68/17hr. = 4hr. |

Akash U. said: (Jan 25, 2014) | |

(Total speed)downstream = Speed of boat + Speed of stream. Time = Distance/speed. |

Wangdeep Tamang said: (Mar 22, 2014) | |

Speed in Still water = 13 km/h. Speed of the stream = 4 km/h. Downstream = 13+4 = 17km (speed in Still water + speed of the stream). Time Take = 68/17 = 4 hrs. |

Manikyam said: (Apr 7, 2015) | |

How to know particularly which formula to use whether downstream or upstream? Bit confusing? |

Somya said: (May 27, 2015) | |

It is given in the question to find time taken to go 68 km downstream. |

Srikanth said: (Jun 24, 2015) | |

Downstream speed = a. Upstream speed = b. Stream speed = 1/2 (a-b)----Formula. Boat speed = 1/2 (a+b)-----Formula. Given boat speed = 13. Stream speed = 4. So 1/2(a+b)+1/2(a-b) = 13+4. ==> a=7. Given D = 68km. D = S*T. Ta = D/Sa. =>68/17. =>4. So time taken by the boat to go 68 km downstream is 4 hrs. |

Prassanna.S said: (Aug 19, 2015) | |

Thanks for giving the correct answer. |

V!Cky said: (Sep 6, 2015) | |

Use Speed = Distance /Time formula. Still in water u+v = 13+4 = 17. 68/17 = 4 km/hr. |

Roshan said: (Sep 12, 2015) | |

Still water speed + Boat speed = Total speed (down stream). Time = Distance/Speed. |

Praveen said: (Oct 14, 2015) | |

Still water means? How it has speed? |

Chetan said: (Dec 12, 2015) | |

It means speed of boat in still water is 13 km/h. |

Laxmidhar said: (Dec 16, 2015) | |

Sp of down stream = (13+4) = 17. Time taken = 68\17 = 4 hr. |

Csharad said: (Mar 19, 2016) | |

Here any short cut method for this? |

Kiruthika said: (Jun 28, 2016) | |

Given: Speed in still water U = 13 km/hr, Speed of stream V = 4 km/hr, Distance = 68 km, Time = ? Solution: Time = distance / U+V(downstream speed) => 68/17, => 4 hour. |

Sivananda said: (Jul 7, 2016) | |

Super explanation @Balaji. Thanks. |

Avijit Das said: (Jul 24, 2016) | |

Appropriate explanation, Thanks to all. |

Honey said: (Aug 10, 2016) | |

Good explanation, Thanks to all. |

Gaurank Verma said: (Aug 25, 2016) | |

Since ship is going downstream, Hence, Resultant speed = 13 + 4 = 17 km/h. Now, Time = distance / speed. ==> Time = 68/17 = 4hours. Therefore, the boat will take 4 hrs. To go 68 km downstream. |

Narayana Reddy said: (Sep 23, 2016) | |

Thanks for providing the answer and explanation. |

Raj said: (Jan 19, 2017) | |

Hi, please give me a solution for this question. "A man can row 8 kms in still water. If in a river flowing at 2 km an hour, it takes him 24 minutes to row to a place and come back, how far of is this place?" |

A.Santhosh said: (Apr 2, 2017) | |

Boat -> a kmph& stream-> b kmph A= boat speed at still water B= water speed=rate of current=stream speed. Along with the flow, Dss(downstream speed) = a+b, Againist with the flow, Uss(upstream speed) = a-b. So, a + b = 13 + 4 = 17, Distance = 68 km, Time = Dist/Uss, T = 68/17 = 4hrs. |

Vadivel said: (Apr 6, 2017) | |

Thaks for explaining the answer friends. |

Birla Jyothi Swaroop said: (Apr 27, 2017) | |

Perfect Explanation, thank @Santhosh. |

Ardhendu Sikdar said: (Jun 17, 2017) | |

13+4 = 17km/hr. Now, 48/17 = 4hr. |

Mythu said: (Jul 26, 2017) | |

Thanks for all your explanations. |

Elizabath said: (Mar 13, 2018) | |

Give a clear explanation to get it. |

Sheetul said: (Sep 9, 2018) | |

Thank you so much @Balaji. |

Gauravbagul said: (Nov 18, 2018) | |

13+4 = 17km/hr, For 1 hour he goes 17 km. Then for 68 km he takes 4 hrs. |

Md Abdul Khabir said: (Jul 30, 2019) | |

Thank you all for explaining it clearly. |

Venky said: (Aug 1, 2019) | |

Thanks to all for giving an explanation. |

Bhushan Roy said: (Sep 6, 2019) | |

Thanks for the nice explanation. |

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