Question

A boat streaming from a point in downstream. Before streaming boatman throw a piece of wood in stream
which moves with the speed of stream. After covering the distance of 100 km, the boatman returns and
picked up the wood. If the speed of the boat in still water is 36 kmph and speed of stream is 9 kmph. Find
the distance covered by the piece of wood.



1.20 km
2.40 km
3.60 km
4.80 km
5.50 km​

Answer 1

Answer:

the distance covered by the piece of wood = 40 km

Step-by-step explanation:

Let say the distance covered by the piece of wood. = D km

Distance Covered by Boat = 100 km  Downstream  + 100 - D  km upstream

Speed of Boat Downstream = 36 + 9 = 45 km/Hr

Speed of Boat Upstream = 36 - 9 = 27 km /Hr

Time of travel by wood = Time of travel by Boat

=> D/9  =  100/45  + (100-D)/27

=> D  = 100/5  + (100 - D)/3

=> 3D = 60 + 100 - D

=> 4D = 160

=> D = 40

the distance covered by the piece of wood = 40 km

Answer 2

$\texttt{Hey\:Brainly\:user}$

$\texttt{Here\:is\:your\:answer}$

$\boxed{\red{\textrm{Answer=40km}}}$

$\rule{300}{2}$

$\boxed{\blue{\texttt{Given}}}$

$\leadsto$ ${\pink{\textsf{Distance=100km}}}$

${\pink{\textsf{speed\:of\:the\:boat\:in\:still\:water=36kmph}}}$

$\leadsto$ ${\pink{\textsf{speed\:of\:the\:stream=9Kmph}}}$

$\rule{300}{2}$

$\boxed{\blue{\mathbb{Solution}}}$

${\red{\textsf{Distance\:travelled\:by\:the\:boat=xkm}}}$

${\red{\textsf{Speed\:of\:downstream=36+9=45kmph}}}$

${\red{\textsf{Speed\:of\:upstream=36-9=27kmph}}}$

$\red{\frac{x}{9}=\frac{100}{45}+\frac{(100-x) }{27}}$

$\red{x=\frac{100}{5}+\frac{100-x}{3}}$

$\red{x=\frac{60+100-x}{3}}$

$\red{3x=60+100-x}$

$\red{4x=160}$

$\red{x=40km}$