LSAT 158 | Section 2 | Logical Reasoning: Q25

LR Question 25 Explanation

QUESTION TEXT: If you complete 24 graduate credits and a thesis …

QUESTION TYPE: Parallel Reasoning

CONCLUSION: Roger hasn’t finished his thesis.

REASONING:

1. If 24 credits AND thesis -> eligible for master’s.
2. Roger has completed 24 credits yet isn’t eligible for a master’s.

ANALYSIS: This structure is pretty straightforward. The rule gives us two requirements. Roger has one of them, but not the final result. So the argument infers that he must be missing the other requirement.

The reasoning works like this: If A and B -> Result. We know A happened, but the result did not. So B did not happen.

We’re looking for an answer that has the same structure.

___________

1. CORRECT. This follows the same structure: if A (mayor approval) and B (council approval) -> gardens open. We have B, but gardens haven’t opened. So we must not have A.
2. This gives an either/or outcome and then uses the fact that one option is false to predict the other. That’s not the same structure.
3. Tempting, but not the same. The sufficient condition is A or B. We needed A and B.
4. Again, this is working with “or” whereas the stimulus is “and”.
5. Same as C and D, “or” instead of “and”.