Question

A boat covers a certain distance downstream in 5 hours but takes 8 hours to return upstream to the starting point. If the speed of the stream be 3 km/hr, what is the speed of boat in still water?​

Answer 1

8 km per hour a boat take

Answer 2

Step-by-step explanation:

let distance 40km

we will get downstream speed= 40km/5hours= 8km/h

simlarly we will get upstream speed= 40km/8hour= 5km/h

now we know that Downstrem speed( speed of boat+ speed of cureet)

=8km/h

upstream speed( speed of boat - speed of current) = 5km/h

now boat= 8+5/2 = 6.5unit

now coreent= 8-5/2= 1.5 unit

and we have given in question 1.5 unit acutulay is 3km/h its means we have to multiply the 6.5×2 = 13km/h to get the speed of boat

note speed if current,strem is same