respective ratio of speed of boat in upstream and downstream is 4:9. what is the respective ratio of speed of boat in still water and speed of current
Answers
Answered by
0
Let the speed upstream be x.
The speed downstream according to the ratio is :
9/4x
Speed upstream = speed of the boat in still water - speed of the river
Speed downstream = speed of the boat in still water plus speed of water in the river
The speed of the stream can be y then :
Speed of the boat = x + y (for the upstream)
Speed of boat = 9/4x - y (downstream)
We equate the two :
9/4x - y = x + y
9/4x - x = y + y
5/4x = 2y
5x = 8y
x/y =8/5
x : y = 8 : 5
Speed of boat upstream : speed of water = x : y
= 8 : 5
Now let speed of current be x.
Speed of boat upstream = 8/5x
Speed of boat = 8/5x + x = 13/5x
13/5x ÷ x = 13/5
The ratio is thus :
13 : 5
Similar questions