A diver rowing at the rate of 5 km/h in still water takes double the time in going 40 km upstream as in going 40 km downstream. Find the speed of the stream.
Answers
Answer:
5/3 km/h
Step-by-step explanation:
Speed in still water = 5km/h
Define x:
Let the speed of the steam be x
Upstream speed = (5 - x) km/h
Downstream speed = (5 + x) km/h
Time taken going upstream:
Time taken = Distance ÷ Speed
Time taken = 40/(5 - x) h
Time taken going downstream:
Time taken = Distance ÷ Speed
Time taken = 40/(5 + x) h
Solve x:
The time taken upstream is double the time taken downstream
40/(5 - x) = 2 (40/(5 + x))
40/(5 - x) = 80/(5 + x )
40(5 + x) = 80( 5 - x)
200 + 40x = 400 - 80x
120x = 200
x = 200 ÷ 120 = 5/3
Answer: The speed of the stream is 5/3 km/h
Answer:
Step-by-step explanation:
Speed in still water = 5km/h
Define x:
Let the speed of the steam be x
Upstream speed = (5 - x) km/h
Downstream speed = (5 + x) km/h
Time taken going upstream:
Time taken = Distance ÷ Speed
Time taken = 40/(5 - x) h
Time taken going downstream:
Time taken = Distance ÷ Speed
Time taken = 40/(5 + x) h
Solve x:
The time taken upstream is double the time taken downstream
40/(5 - x) = 2 (40/(5 + x))
40/(5 - x) = 80/(5 + x )
40(5 + x) = 80( 5 - x)
200 + 40x = 400 - 80x
120x = 200
x = 200 ÷ 120 = 5/3
Answer: The speed of the stream is 5/3 km/h
Step-by-step explanation: