#7 - Library policy: For a book to be removed from

[Administrator]

Complete Question Explanation

Justify the Conclusion. The correct answer choice is B.

The library policy is that, for a book to be removed (BR), that book must be badly damaged (BD) AND not checked out for over two years (O2Y). This could be diagrammed as:

If BR BD + O2Y

However, books written by local authors (WLA) or of significance to local history (SLH) can only be removed (BR) if they haven't been checked out for over THREE years (O3Y). You can diagram this complex conditional like this, but diagramming is not necessary to the question.

If BR and [WLA or SLH] O3Y

The application of the rule states that Paper Flowers should not be removed from circulation. The question stem asks which of the following, if true, justifies that fact.

Answer Choice (A): We know PF is badly damaged, but we do not have information on when it has been most recently checked out. Without that information, we cannot justify the application.

Answer Choice (B): This is the correct answer choice. Both the first and second conditionals require a book to not have been checked out for over 2 or 3 years, respectively. If PF has been checked out within 1 year, it cannot be removed, according to these rules. This information makes (B) the correct answer.

Answer Choice (C): This answer choice has the same issue as answer choice (A). We learn that PF was last checked out over 2 years ago, but we do not know whether it was badly damaged or not, or if it is written by a local author, or if it's of significance to local history. Therefore, we cannot justify the application.

Answer Choice (D): If PF was written by a local author, it can only be removed if it hasn't been checked out in over 3 years. However, we don't know how recently it has or hasn't been checked out.

Answer Choice (E): This answer choice is effectively the same as answer choice (D). Again, we do not know how recently PF has been checked out, so we cannot definitively say it shouldn't be removed.

[eg_m]

Can someone diagram the conditional logic for the 2nd sentence?

LA or SLH
      and           Cow3y
removed

[Adam Tyson]

I like your diagram, eg_m! You've got everything covered there, and it should work well. The contrapositive would read something like "if a book has been checked out within the past 3 years, then it either cannot be removed from circulation or else it is not written by a local author and is not significant to local history."

Another option here is to do a nested conditional, which means a conditional statement is placed within a larger conditional statement. That could go like this:

LA

or (Cow3y removed)

SLH

There's other ways to do it, too, with variations on the contrapositives. For example, in the parentheses in my necessary condition I could have instead written (removed Cow3y).

Work within the confines of what the language logically requires, keeping your sufficient and necessary conditions straight, but within that framework there can be some flexibility. You did it right!

[medialaw111516]

I diagrammed mine that way and got it right, but am slightly worried whether or not I'm looking at this correctly.

After reading the premise, I noticed that both conditions had the element of time. So, my prephrase was that the only reasons paper flowers would not be removed in the first case are
1. If it was not badly damaged
or 2. if it was checked out more 2 years ago or more recently

In the second case, it would only not be removed if it was checked out 3 years ago or more recently.

B fell into both of those time categories so I picked it, but is time the crucial element here like I prephrased?

[Claire Horan]

Hi MediaLaw,

You are right that time is a key element because, if you don't know how long it has been since the book was checked out, you cannot say definitively that it should not be removed from circulation.

Your prephrase is incorrect because the conditions do not require a book to be removed from circulation. They specify when a book CAN be removed from circulation.

I think the reason for your mistake is that you made it overly complicated, and I think you can approach the question in a more straightforward way. The application of the rules leads to the conclusion that Paper Flowers should not be removed, so we are looking for the answer choice that, by itself, leads to that conclusion. A book is not removable if it is not badly damaged or if it has been checked out within two years. We can ignore the other conditional for a moment because, if either of these are present in the answer choices, we are done. B says the book has been checked out in the last year, and that's sufficient to know that it's not removable. The diagramming is interesting on this one, but having to navigate two conditionals may have confused you.

Good luck with your studying!

[theamazingrace]

I spent a lot of time on this question trying to decide between B and C. Since the application does not specify what type of book it is C is wrong because 2.5 years only applies to the books that were either written to local authors or were considered to be of significance to local history and not to regular books? Is my thinking correct?

Thanks!

[Adam Tyson]

Correct, theamazingrace. In order to prove that the book should not be removed from circulation we would need to know more about it. All we know from answer C is that it was checked out between two and three years ago, but we would need to also know that it is not badly damaged, or that it was written by a local author, or that it is of significance to local history. Since we have none of that information, we cannot conclude that it should not be removed.

[gabyd33]

What question type is this? I am struggling to categorize it.

[atierney]

Yes, this is a Justify the Conclusion question, where we are looking for an answer that is "sufficient" to prove the conclusion correct. A good way to identify these is look for the word "justify" in the question stem, and here it is accompanied by the word "fully," thereby indicating a sufficiency requirement.

[jailenea]

Can someone please help with diagramming the second conditional? It seems to be compound, and I'm confused. Also, do you this diagram is necessary to not spend too much time on the question?