Question

Say you go kayaking over a 2 mile stretch of river. The river is flowing at a speed of 1mph. You go 2 miles upstream, and then 2 miles downstream, back to your starting point, for one round trip. What would your average speed be if that round trip took 1 hour? (show all work)

Answer 1

my average speed = 4 miles per hour (4 mph)

Explanation:

Extracting the key information from the question:

*** I went kayaking over a 2mile stretch of river.

*** I went 2 miles upstream

*** I also went 2 miles downstream back to origin.

*** I am only required to complete my average speed if the round trip took 1 hour.

The total distance that was covered in the round trip (my upstream and downstream journeys) is:

= 2 miles [upstream] + 2 miles [downstream].

= 4 miles for the round trip.

Again, we were informed that I spent 1 hour going upstream and downstream.

This means that the round trip time = 1 hour.

Average speed is simply = total distance covered/total time taken

Here, total distance covered = 4 miles.

Total time taken = 1 hour

Average speed = 4 miles/1 hour = 4 miles per hour