A boat whose speed in still water is 18 kilometre per hour takes 1 hou...
Problem:
A boat whose speed in still water is 18 kilometre per hour takes 1 hour more to go 24 km upstream then to return downstream to the same spot find the speed of the stream?
Step 1: Understand the problem
The problem describes a boat that moves upstream and downstream at different speeds, which is affected by the speed of the stream. We need to find the speed of the stream.
Step 2: Formulate the equations
Let's assume the speed of the stream is x km/h.
Speed downstream = (18 + x) km/h
Speed upstream = (18 - x) km/h
Time taken upstream = Time taken downstream + 1 hour
Distance traveled upstream = Distance traveled downstream
Distance = Speed x Time
24 = (18 + x) x t1
24 = (18 - x) x (t1 + 1)
Step 3: Solve the equations
Let's solve the equations to find the value of x.
24/(18 + x) = t1
24/(18 - x) = t1 + 1
24 = t1(18 + x)
24 = (t1 + 1)(18 - x)
Substitute t1 from equation 1 to equation 3
24 = (24/(18 + x))(18 + x)
24 = 24
Substitute t1 from equation 2 to equation 4
24 = (24/(18 - x))(18 - x + 18)
24 = (24/(18 - x))(36)
18 - x = 12
x = 6 km/h
Step 4: Check the answer
Let's check the answer by substituting x = 6 in the equations.
Speed downstream = (18 + 6) = 24 km/h
Speed upstream = (18 - 6) = 12 km/h
Time taken downstream = 24/24 = 1 hour
Time taken upstream = 24/12 = 2 hours
Distance downstream = Speed downstream x Time = 24 x 1 = 24 km
Distance upstream = Speed upstream x Time = 12 x 2 = 24 km
The answer is correct.
Step 5: Conclusion
The speed of the stream is 6 km/h.