As.1997
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#1
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Please have a look at the attachment.
The answer is D.
Can someone please explain how they get D. I was able to eliminate A,C, B,
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mqb2766
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The cross, circle and stripe all share a vertex and the stripe "points" to the cross.
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ChloeHemmings290
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(Original post by As.1997)
Please have a look at the attachment.
The answer is D.
Can someone please explain how they get D. I was able to eliminate A,C, B,
(Original post by As.1997)
Please have a look at the attachment.
The answer is D.
Can someone please explain how they get D. I was able to eliminate A,C, B,
(Original post by As.1997)
Please have a look at the attachment.
The answer is D.
Can someone please explain how they get D. I was able to eliminate A,C, B,
I’m not somebody that does very well in maths, however I noticed that on this net, when it’s made, the two circles will never connect correctly with the cross and the line. The triangle will always be on the bottom of the cube if the open circle is on the top. For E, for the cube to be in the position it is in, the filled circle must be next to the vertical line, however it is next to the horizontal line. If this is wrong I apologise however that is what I managed to work out. I hope this helped
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As.1997
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(Original post by mqb2766)
The cross, circle and stripe all share a vertex and the stripe "points" to the cross.
Using this, idea it limits it to two options: C and D
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As.1997
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(Original post by ChloeHemmings290)
I’m not somebody that does very well in maths, however I noticed that on this net, when it’s made, the two circles will never connect correctly with the cross and the line. The triangle will always be on the bottom of the cube if the open circle is on the top. For E, for the cube to be in the position it is in, the filled circle must be next to the vertical line, however it is next to the horizontal line. If this is wrong I apologise however that is what I managed to work out. I hope this helped
Hey, thanks for your observations. I'm still struggling to get to the answer
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mqb2766
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(Original post by As.1997)
Using this, idea it limits it to two options: C and D
C is wrong. Remember there are two stripes. This stripe must be the left hand one on the second row. It "points" to the wrong object.
The stripe for D must be the right hand one on the second row. The two stripes are on opposing faces.
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As.1997
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(Original post by mqb2766)
C is wrong. Remember there are two stripes. This stripe must be the left hand one on the second row. It "points" to the wrong object.
The stripe for D must be the right hand one on the second row. The two stripes are on opposing faces.
Ahh okay, I get you
When you tackle these do you use a combination of vertices that touch, opposing shapes, and visualization of the different sides in your head?
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mqb2766
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(Original post by As.1997)
Ahh okay, I get you
When you tackle these do you use a combination of vertices that touch, opposing shapes, and visualization of the different sides in your head?
A few different things. All that you mention and if the sides are two apart on the net (seperated by one side), theyre opposite faces so cant appear on the same view of the cube. The orientation (like in this question) of shapes is also important.
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As.1997
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Fair enough -- Will keep this in mind.
I'm now having trouble to rule out E.
It looks okay atm to me :l
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mqb2766
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(Original post by As.1997)
Fair enough -- Will keep this in mind.
I'm now having trouble to rule out E.
It seems to be correct.
The triangle is on the top, given the other two faces.
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As.1997
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(Original post by mqb2766)
The triangle is on the top, given the other two faces.
I thought having the black circle at the front face and the blank circle on the top would mean the triangle is on the bottom.
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If you assume two are correct, you can argue the third isn't. It doesnt really matter which 2 you pick, but I did the ones that correspond to the 3 bottom right faces on the net. Saves a bit of mental gymnastics with folding the full net.
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As.1997
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(Original post by mqb2766)
If you assume two are correct, you can argue the third isn't. It doesnt really matter which 2 you pick, but I did the ones that correspond to the 3 bottom right faces on the net. Saves a bit of mental gymnastics with folding the full net.
If you fold the net outwards concentrating on the bottom 3, it would show that C should have a triangle at the top.
But, what if you fold the shape inward, such that the blank circle is on the top, isn't this also possible?
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(Original post by As.1997)
If you fold the net outwards concentrating on the bottom 3, it would show that C should have a triangle at the top.
But, what if you fold the shape inward, such that the blank circle is on the top, isn't this also possible?
Sure. I suppose checking for
* opposing faces
* 3 faces sharing a vertex
* relative face orientation
Is the way to go. We had just assumed different sets of 2 correct faces and checking the third. This net is deliberately a touch trickier because of the stripes on two of the faces.
Tbh, take a pair of scissors and fold the net up.
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As.1997
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(Original post by mqb2766)
Sure. I suppose checking for
* opposing faces
* 3 faces sharing a vertex
* relative face orientation
Is the way to go. We had just assumed different sets of 2 correct faces and checking the third. This net is deliberately a touch trickier because of the stripes on two of the faces.
Tbh, take a pair of scissors and fold the net up.
I think I'm going to have to get the scissors.
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mqb2766
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(Original post by As.1997)
I think I'm going to have to get the scissors.
Tbh, they often give you a bit of a hint. B and E are wrong for similar reasons if you concentrate on the bottom right 3 cells in the net.
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As.1997
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Okay, now I know why it is E. So for these type, you cannot fold inwards. Please have a look at the attachment to see what I mean by inwards, so you can reject my finding if you believe I am wrong.
Based on this rule, it would tell us that E is wrong and D is right.
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mqb2766
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(Original post by As.1997)
Okay, now I know why it is E. So for these type, you cannot fold inwards. Please have a look at the attachment to see what I mean by inwards, so you can reject my finding if you believe I am wrong.
Based on this rule, it would tell us that E is wrong and D is right.
Thats correct. I missed what you meant by inwards earlier. its the net of a cube, so outwards only;
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As.1997
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(Original post by mqb2766)
Thats correct. I missed what you meant by inwards earlier. its the net of a cube, so outwards only;
Perfect. Now, I believe I understand all the rules for these net-type questions and all the skills needed to work it out.
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(Original post by As.1997)
Perfect. Now, I believe I understand all the rules for these net-type questions and all the skills needed to work it out.
And if not, a pair of scissors ...
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