A man can row a boat at a speed of 8, km/h in | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) Let the total distance between the two points be $d\, km$.Speed of the boat in still water = $8\, km/h$.Speed of the stream = $2\, km/h$.Downstrea

Vedclass · Accepted Answer

$30$

Vedclass · Answer

(B) Let the total distance between the two points be $d\, km$.Speed of the boat in still water = $8\, km/h$.Speed of the stream = $2\, km/h$.Downstream speed = $8 + 2 = 10\, km/h$.Usual time taken to cover distance $d$ downstream = $\frac{d}{10}$.In the actual scenario,the man travels half the distance $(d/2)$ at $10\, km/h$ and the remaining half $(d/2)$ at the speed of the stream $(2\, km/h)$ because the motor failed.Actual time taken = $\frac{d/2}{10} + \frac{d/2}{2} = \frac{d}{20} + \frac{d}{4} = \frac{d + 5d}{20} = \frac{6d}{20} = \frac{3d}{10}$.Given that the actual time is $6\, hours$ more than the usual time:$\frac{3d}{10} - \frac{d}{10} = 6$$\frac{2d}{10} = 6$$\frac{d}{5} = 6$$d = 30\, km$.

Similar Questions

$A$ man can row $7 \frac{1}{2} \, km/hr$ in still water. If in a river running at $1.5 \, km/hr$,it takes him $50 \, minutes$ to row to a place and back,how far off is the place? (in $km$)

$A$ sailor goes $12$ $km$ downstream in $48$ $min$ and returns in $1$ $h$ $20$ $min.$ The speed of the sailor in still water is..........$km/h$.

Speeds of a boat along the current and against the current are $10 \ km/hr$ and $8 \ km/hr$ respectively. What is the speed (in $km/hr$) of the current?

$A$ boatman rows $1\, km$ in $5\, min$ along the stream and $6\, km$ in $1\, h$ against the stream. The speed of the stream is in $km/h$:

$A$ man can row $30 \text{ km}$ upstream and $44 \text{ km}$ downstream in $10 \text{ hours}$. Also,he can row $40 \text{ km}$ upstream and $55 \text{ km}$ downstream in $13 \text{ hours}$. Find the rate of the current and the speed of the man in still water.

Vedclass Test Series

Exam Paper Generator

Online Exam Module