# Average speed of Boat in Upstream and Downstream Calculator

A person rowing a boat in the still water in a particular speed will not be same as that of the rowing speed in stream water. Obviously, on comparing the speed in still water, the speed in downstream will be more and speed in upstream will be less. Here is the simple online average speed of boat in upstream and downstream calculator which provides you the speed of the boat in a stream based on the entered values of speed in still water and speed of stream flowing.

A person rowing a boat in the still water in a particular speed will not be same as that of the rowing speed in stream water. Obviously, on comparing the speed in still water, the speed in downstream will be more and speed in upstream will be less. Here is the simple online average speed of boat in upstream and downstream calculator which provides you the speed of the boat in a stream based on the entered values of speed in still water and speed of stream flowing.

Code to add this calci to your website

#### Formula:

Average Speed of a Boat (km/hr) = ((a + b) x (a - b)) / a
Speed in Downstream (km/hr) = a + b
Speed in Upstream (km/hr) = a - b
**Where,**
a = Speed in Still Water (km/hr)
b = Speed of Stream (km/hr)

### Example:

Calculate the average speed of boat in upstream and downstream with the still water speed of 30 km/hr and speed of the stream of 20 km/hr.

#### Solution:

Average speed of a boat = ( ( 30 + 20 ) x ( 30 – 20 ) ) / 30

= 16.666667 km/hr

speed in downstream = 30 + 20

= 50 km/hr

speed in upstream = 30 – 20

= 10 km/hr