PAT Keyhole: Help!

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MRZ8

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Why do we assume there's a hole in the middle of the object? I thought the given object must show a gray oval-shaped area at the bottom of the circle to denote a hole is present.
Bootcamp.png
 
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I have a similar question... I understand why my choice was wrong but I don't understand why there isn't a hole...View attachment 193243
The correct answer, "D", is actually the top-bottom view, meaning no hole goes through that view as it does in the front-back view. Answer "D" is rotated CCW 90 degrees from the given object. Hope that helps.
 
Why do we assume there's a hole in the middle of the object? I thought the given object must show a gray oval-shaped area at the bottom of the circle to denote a hole is present.View attachment 193241

C isn't close to the right dimensions. So if you couldn't intuitively realize there is a hole, you would by the answer choices.
 
The correct answer, "D", is actually the top-bottom view, meaning no hole goes through that view as it does in the front-back view. Answer "D" is rotated CCW 90 degrees from the given object. Hope that helps.

I understand why D doesn't have a hole, I don't understand why the key says the "back" view doesn't have a hole.
 
Why do we assume there's a hole in the middle of the object? I thought the given object must show a gray oval-shaped area at the bottom of the circle to denote a hole is present.View attachment 193241

Hey, I remember seeing that exact question on DAT bootcamp and having the same question. I asked a friend of mine who took the DAT and this is what he told me. A lot of these DAT prep programs (especially for the PAT) make some errors. On the actual DAT it will be a lot clearer if there is a hole there or not. My experience with the DAT confirms this!! so no worries 🙂
 
Hey, I remember seeing that exact question on DAT bootcamp and having the same question. I asked a friend of mine who took the DAT and this is what he told me. A lot of these DAT prep programs (especially for the PAT) make some errors. On the actual DAT it will be a lot clearer if there is a hole there or not. My experience with the DAT confirms this!! so no worries 🙂
There actually isn't any error in this problem, the reason you can assume there is a hole there is because of rule #4 in the keyhole section on the DAT: "There are no irregularities in any hidden portion of the object. However, if the figure has symmetric indentations, the hidden portion is symmetric with the part shown."

For applications of this rule, check out problems 13 and 14 in the 2007 DAT. You can't directly see there is a hole in 13, there is no gray outline to show it goes all the way through, but you can infer it and apply rule #4 that the hole must continue all the way through. You can also see the rule being applied in problems 2, 5, 6, and 13 of the 2009 DAT keyhole section. As such, we assume the hole goes all the way through for this problem too. Additionally, [C] could be eliminated because it is too thin to fit the shape.

I understand we never explain that rule in the problems and just assume you know it which is my fault, I'll include reasoning on when you can assume there is a hole going through the shape to clear it up for future students.
 
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