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The Dagda
Feb11-09, 04:26 PM
This ones a classic and it doesn't seem it's come up before.

But draw 9 dots in 3 rows and columns that are equidistant, now join them up with not more than 4 straight lines.

If you already know it be sure not to give the game away. Just a simple problem I thought might pass a few moments to those who haven't seen it before.

Proton Soup
Feb11-09, 04:42 PM
i'm not sure i understand the question, because i've already thought of 5 answers

Hurkyl
Feb11-09, 04:59 PM
He forgot to say that the line (segments) have to be drawn contiguously; each line segment begins where the previous one ends.

Rogerio
Feb11-09, 08:42 PM
A solution...

Rogerio
Feb11-09, 09:12 PM
I decided to remove the figure cause there is no "spoiler mode" for figures...

For the points below

................
..1...2...3...
................
..4...5...6...
................
..7...8...9...
................

use these lines:



[3->7] [7->0] [0->10] [10->8]

....................
..0.................
....................
..1...2...3.......
....................
..4...5...6.......
....................
..7...8...9...10
....................


:smile:

DaveC426913
Feb11-09, 09:33 PM
This is the classic think-outside-the-box puzzle.

Proton Soup
Feb11-09, 10:10 PM
ah, yes, i remember it now. even though i remembered the basic strategy, it still took a few tries in my head to arrive at the result.

The Dagda
Feb12-09, 05:36 AM
He forgot to say that the line (segments) have to be drawn contiguously; each line segment begins where the previous one ends.

Oh yes apologies. It must be a continuous line, ie you're not allowed to lift your pen from the paper.

Well done those who got it, yeah it is a classic but it stumps so many people I rather like it. It's one of those puzzles were people impose rules on themselves.