One of These Things is Not Like the Others

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Struggling with this one. What do you think?

Which of the five figures does not share the same basic, common feature that the others share?

http://img12.imageshack.us/img12/7317/spatial1.png

The figures aren't perfectly recreated in the image - assume that the shape in the middle is a perfect square and is centered inside another perfect square. EDIT: image fixed. Terribly sorry for the goof. Also, if this stimulates interest, I've got another I can post.
 
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I think the feature is ...
symmetry
 
Jonathan Scott said:
I think the feature is ...
symmetry

Meaning they're all asymmetric except for B?
 
No.
B is rotationally symmetric. They're all symmetric except D.
 
I'm not seeing the symmetry in A, C, and E. 2 dimensional or 3?
 
Quixotic said:
I'm not seeing the symmetry in A, C, and E. 2 dimensional or 3?
??
They're all mirror symmetry about an axis.
 
D has no symmetry. Look again. Your brain seems to have gas :wink:
 
This is embarrassing... I made a mistake with my image. The bottom half of D should look like the top half. I wasn't looking at my own image, I was looking at the original image in print. :redface:
 
B is the only item that has lines that don't border a square (assuming overlapping squares). A, C, and E are obvious; D takes a tiny bit of diligence.
 
Quixotic said:
This is embarrassing... I made a mistake with my image. The bottom half of D should look like the top half. I wasn't looking at my own image, I was looking at the original image in print. :redface:

OK, in that case the feature is ...
mirror symmetry, and B is the odd one out
 
The second set of figures:

http://img11.imageshack.us/img11/3806/spatial2.png

Same instructions.
 
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B is the only one that cannot be drawn in its entirety with a single, unbroken line.

There is a quick trick to this. Some intersections contain an odd number of spokes. Ergo: endpoints of more than one line.
 
My first guess too, but we're looking for a basic, common feature, and what's even simpler is that

all the figures except C feature triangles.

Or is that too simple?
 
Quixotic said:
My first guess too, but we're looking for a basic, common feature, and what's even simpler is that

all the figures except C feature triangles.

Or is that too simple?

Personally I think my answer is more elegant. I think the answer you gave is too ... trivial.

You could go even simpler and say c is the only one with no diagonal lines.
 
DaveC426913 said:
Personally I think my answer is more elegant. I think the answer you gave is too ... trivial.

You could go even simpler and say c is the only one with no diagonal lines.
Personally I think yours is more elegant also. :smile:
 
I like Dave's answer, but also couldn't an alternative answer be D following the same reasoning as for the first question?