The speed of a boat in still water is 15 km/hr. It can go 45km upstrea

1.	The speed of a boat in still water is 15 km/hr. It can go 45km upstream and return downstream to the original pointin 6 hours and 45 minutes. Find the speed of the stream.nuhi to cover 150 km was 2 hrs 30
Answer» Given - Speed of water = 15km/hr Distance travelled upstream and downstream = 30 km Let, speed of stream be x km/hr So, time taken to travel 30km upstream = 30/15-x and, time taken to travel 30km downstream = 30/15+x Time taken to travel 30km upstream and 30km downstream = 4 hour 30 min or 9/2 hours So, the equation formed will be 30/15-x + 30/15+x = 9/2 => 30(1/15-x + 1/15+x) = 9/2 => 1/15-x + 1/15+x = 9/230 = 3/20 => (15+x+15-x)/225 - x2= 3/20 => 30/225-x2= 3/20 => 225-x2= 3020/3 =>225-x2= 200 => x2= 225-200 => x2= 25 =>x = 5 But, x = speed of stream So, speed of the stream = 5 km/hr

The speed of a boat in still water is 15 km/hr. It can go 45km upstream and return downstream to the original pointin 6 hours and 45 minutes. Find the speed of the stream.nuhi to cover 150 km was 2 hrs 30

Answer»

Given -

Speed of water = 15km/hr

Distance travelled upstream and downstream = 30 km

Let, speed of stream be x km/hr

So, time taken to travel 30km upstream = 30/15-x

and, time taken to travel 30km downstream = 30/15+x

Time taken to travel 30km upstream and 30km downstream = 4 hour 30 min or 9/2 hours

So, the equation formed will be

30/15-x + 30/15+x = 9/2

=> 30(1/15-x + 1/15+x) = 9/2

=> 1/15-x + 1/15+x = 9/2*30 = 3/20

=> (15+x+15-x)/225 - x2= 3/20

=> 30/225-x2= 3/20

=> 225-x2= 30*20/3

=>225-x2= 200

=> x2= 225-200

=> x2= 25

=>x = 5

But, x = speed of stream

So, speed of the stream = 5 km/hr