Lori mentioned there are methods to account for not taking a direct route to a destination. This brainteaser will help a person learn these methods. The first time it can be done on a piece of paper. Then in a big open area using vectors of your choice. A protractor would be real handy so you don't have to orient the map each time.

Your destination is 1,000 feet straight north of your current position.

Due to simulated obstacles, you have to walk the following distances and headings:

Heading dist (Feet)
30_____ 100
280____ 150
45_____ 200
360____ 75
290____ 100
90_____ 150
350____ 200

What is you bearing and distance to the destination?