Q12 - It is clear that none

[peg_city]

I really struggled with the inferences on this one, although I guessed right.
I have the second inference backwards on one of them. What am I doing wrong?

Volleyball players -> badly sunburned
came to work -> ~Badly sunburned
Volleyball players -> ~came to work

D)
Office on second floor -> worked with president
Works for president -> ~July Vacation
Office on second floor -> ~July Vacation

Thanks

[giladedelman]

You're not doing anything wrong. You're just forgetting that a conditional statement and its contrapositive are 100% interchangeable. The stimulus and (D) have the same logical structure (wonderfully diagrammed in your post), but the second premise is phrased slightly differently. You could just as easily have diagrammed (D) as

Office on second floor -> works for president
July vacation -> ~works for president
Office on second floor -> ~July Vacation

Then it would more obviously match the stimulus. Make sense?

As a side note, the nice thing about this question is that since the argument in the stimulus is logically valid, we can get rid of any answer that is not. That ends up getting rid of everything but (D)!

(A) is bad because one of the premises is about all the employees who are offered insurance, but then the conclusion tries to be about all the employees in general, which doesn't work.

(B) is old-school reversed logic.

(C) is out because having a reputation for being on time is not a binding conditional relationship.

(E) is reversed logic, and not all conditional statements.

[redcobra21]

Hey

I had a question about this problem. For parallel reasoning questions, isn't it the case that the answer choice's method of reasoning needs to be the same as the stimulus's? I understand that the contrapositive is the logical equivalent, but if the stimulus takes the extra step of taking a contrapositive to reach its conclusion while the answer choice does not, doesn't this mean that they did not use the same method of reasoning?

Thanks

[tommywallach]

The contrapositive isn't an extra step. It is the same statement, but worded in a different way. These questions only want to match the reasoning. One thing that might help, notice that the correct answer and the original stimulus both have two "none/no one" premises and one "everyone" premise. They really are the same!