Question

plzzz answer it urgently.....

Answer 1

Answer:

plz Mark as brainlist answer

Step-by-step explanation:

Speed of the boat in water =.5 km/hr

Let the speed of the stream be x km/hr

So, the speed of the boat upstream will be

(5-x) km / hr

So, the speed of the boat downstream is (5+x)

k/hr

Time given to cover 40 km upstream = 3(time

taken to cover dowmstream)

⇒40/ (5-x) km/hr = 3(5+x)

⇒1/(5-x)=3(5+x)

⇒5+x=15-3x

⇒x+3x=15-5

⇒4x=10

⇒X=10/4

⇒X=5/2

∴x=2.5 km/hr

plz follow me

mark as brainlist answer

Answer 2

Answer:

15 km/hour

Step-by-step explanation:

downstream=} distance = 40 km

                       let time taken in downstream be x hours.

                        speed = distance/time = 40/x kmph

upstream=} distance = 40 km

                           then time taken in upstream = 2x hours.

                           speed = distance/time = 20/x kmph

speed of boat in still water = 5 kmph

downstream = speed of stream + speed of boat

                     = 40/x kmph

therefore speed of stream = 40/x kmph - 5 kmph

upstream = speed of stream - speed of boat

                = 20/x kmph  

therefore speed of stream =20/x kmph = 20/x kmph + 5 kmph

now,  speed of stream = speed of stream

                   20/x + 5 = 40/x - 5

                    40-5x = 20 + 5x

                         10x = 20

                             x =2

speed of stream = 20/x + 5 = 10 +5 = 15 kmph

like kar diyo dear.