#21 -Any student who is not required to hand in written

[Arindom]

Hi,

I had some difficulty with question and selecting answer. Could you check my diagramming and see where I am going wrong? Or if there is a better way to plug in the right answer?

So -
Premise 1: Student not required to hand in written homework ---> not complete all reading assignments
Premise 2: Student not required to hand in written homework ---> even highly motivated students will neglect their reading assignments
Conclusion: students are given several reading assignments and no written assignments ---> no student will receive a high grade for the course

If this diagramming is correct how do I plug in ans. choice a which if I have diagrammed it correctly is -
student who completes anything less than all of the reading assignments---> receive a high grade

Thanks.

- Arindom

[Clay Cooper]

Hi Arindom,

Thanks for another good question.

Your diagramming and analysis are good until you arrive at the diagram of answer choice A. Instead of what you have written, it should be:

Don't complete all reading assignments Don't get high grade

Or, the contrapositive:

Get high grade Completed all reading assignments.

With this correct version of the diagram of answer choice A, it becomes clear that the author of the stimulus has assumed in making his or her argument that no one can receive a high grade unless they do all the reading. With that piece in place, the argument is sound.

We could confirm our answer using the negation technique; if it were not the case that you won't receive a good grade unless you complete all of the reading assignments, then this author's reasoning is flawed and the argument falls apart.

I hope that helps.

[EmilyLSAT22]

I understand why A is correct, but why is D wrong? Thank you!

[Malila Robinson]

Hi Emily,
Answer choice D is a mistaken negation of the second sentence, which makes it an incorrect answer.
Hope that helps!
-Malila

[marshallmg]

Hello!

I'm very tripped up by this question and I'm having a hard time seeing how answer choice A works for this justify question.

I have the premises and conclusion diagrammed as

Premise: NOT required to hand in written homework --> NOT complete reading assignments

Conclusion: Given reading assignments AND NOT given written homework --> NOT receive high grade

I see from the previous post that answer choice A is diagrammed as NOT reading assignments --> NOT high grade. Would someone mind taking the time to explain how this logically completes the argument? Thank you!!

[Jeremy Press]

Hi Marshall,

Let's make a slight adjustment to your diagram of the premises and answer choice A, just to make it easier to see how it "connects" to the premise of the argument that you've diagrammed. Let's diagram the premise as:

NOT required to hand in written homework --> NOT complete all reading assignments

Let's diagram the conclusion as:

NOT complete all reading assignments --> NOT high grade

Hopefully you'll agree with me that those diagrams are just a bit more comprehensive, but accurately reflect the content of both the premise and answer choice A.

With those diagrams we get this linked chain:

NOT required to hand in written homework --> NOT complete all reading assignments --> NOT high grade.

That chain justifies and in a sense mirrors the conclusion, which states that if the students have some reading assignments and NO written assignments (i.e., they're not required to hand in written homework), they will NOT receive a high grade in the course. How do we know for sure they won't get the high grade? Because now from the premise we know without the written homework, they won't complete all the reading they're given, and without completing all the reading they're given, they won't get high grades.

I hope this helps!

Jeremy

[floydbtric@gmail.com]

How do we know we can assume that "several" is equivalent to "all" in the diagraming of the reading assignments?

[Jeff Wren]

Hi floyd,

The term "all of the reading assignments" in the premise refers to all of the reading assignments that were assigned in the course, so if a course assigns "several" reading assignments, those would be "all of the reading assignments" that were assigned. In other words, "several" is just referring to the general number of reading assignments that were assigned in the course rather than a subset of the reading assignments. If the term has been stated "several of the reading assignments," this would not imply all of the reading assignments.

Also, in the conclusion, the key term is actually that there are "no written assignments," which is equivalent to (and should be diagrammed the same as) the "not required to hand in written homework" term in the premise. Based on the first conditional premise, we know that if students are "not required to hand in written homework," then they "will not complete all the reading assignments." The fact that the conclusion mentions that the course has several reading assignments is largely extraneous, perhaps it's just to establish that there were in fact reading assignments in the course (because if there weren't any reading assignments, then the premises really wouldn't apply).