War & Peace

Probability Level 2

9 trenches are arranged in a square and connected by paths along what would be the grid lines. The central trench is heavily mined.

One commander, at one corner of the square, wants to send a peace offer to the enemy commander, who is at the opposite corner. How many different ways can the emissary walk to the enemy commander without retracing his steps or getting blown up by the mines in the central trench?

4 3 1 2

Denton Young by Denton Young , 47, USA

This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try refreshing the page, (b) enabling javascript if it is disabled on your browser and, finally, (c) loading the non-javascript version of this page . We're sorry about the hassle.

1 solution

Denton Young
Jun 15, 2016

The emissary can walk around the perimeter clockwise, or around the perimeter counterclockwise. All other options run into the mines.

1 Helpful 0 Interesting 0 Brilliant 0 Confused

It might be worth mentioning that the emissary can only enter any given trench once, (otherwise he could potentially retrace his steps, which would make the answer infinity.)

Brian Charlesworth - 5 years ago

Log in to reply

I took your advice.

Denton Young - 5 years ago

Log in to reply

I had a lot of difficulty understanding the problem. To me, a "trench" would be the path that connects two "nodes". The phrasing of

9 trenches are arranged in a square and connected by paths along what would be the grid lines.

could be greatly clarified.

Calvin Lin Staff - 4 years, 12 months ago

0 pending reports

×

Problem Loading...

Note Loading...

Set Loading...