Originally Posted by

**Soroban** Hello, mathbuoy!

This is a classic puzzle.

There is a point $\displaystyle \,A$ near the South Pole.

He walk 2 km south to point $\displaystyle \,B.$

When he walks 2 km east, he walks *around the earth* and returns to $\displaystyle \,B.$

. . (The circumference of the circle of latitude is exactly 2 km.)

Then he walks 2 km north and arrives at $\displaystyle \,A.$

Actually point $\displaystyle \,A$ can be any point on *its* circle of latitude.

. . Hence, there are brizillians of possible starting points.

We can also locate point $\displaystyle \,A$ so that he walks 2 km south to point $\displaystyle \,B.$

Then when he walks 2 km east, he *walks around the earth twice.*

Get it?