Logical Reasoning

PT140 · S3 · Q24 If the concrete is poured while

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If the concrete is poured while the ground is wet, it will not form a solid foundation.

Conclusion (So)

If concrete settles evenly, either it as poured while the ground was dry or it will crack.

Evidence

If the concrete is poured while the ground is wet, it will not form a solid foundation.

If the concrete doesn't form a solid foundation, it will settle unevenly or crack.

Evaluate

Since both premises and the conclusion are all conditionals (and since we see repeating symbols like "ground is wet" / "solid foundation" / "settle evenly"), we should convert this into some algebra.

If the concrete is poured Gw → ~Sf while the ground is wet, won't form a solid foundation.

If not form solid foundation, ~Sf → ~Se or C settle unevenly or crack

If concrete settles evenly, Se → ~Gw or C ground was dry or crack

We have to make sure we're seeing "ground is wet / ground is dry" as the same symbol, just with two different truth value, and we have to see "settle evenly / settle unevenly" as well as logical opposites (two sides of the same coin).

Ideally, our abstract algebra is in generic variables, not ones that match the subject matter of the stimulus argument.

Goal

So, we need two conditional premises, which should chain together, the second of which should have an "or" outcome. Premise 1: A → B Premise 2: B → C or D

Our conclusion should start with the opposite of one of the "or" ideas (C or D). And then it should also have an "or" outcome, combining the opposite of the trigger from the first conditional (A) and the other half of the "or" outcome (whichever one of C/D we didn't use).

Conc: ~C → ~A or D

24.

Which one of the following arguments is most closely parallel in its reasoning to the reasoning in the argument above?

  1. Correct

    The film will not be

    Why this is right

    This has three conditionals. The two premises chain together. One of the premises has an "or" outcome, and so does the conclusion. Those factors would be enough for us to see this is the correct answer. Here's a more detailed breakdown. Premise 1: A → B cam not → film not work prop prop exp Premise 2: B → C or D film not → blurred or dark prop exp Conclusion: ~C → ~A or D ~blurred → work prop or dark

    Skill tested: Parallel · how this choice captures the argument's function is the move to repeat next time.

    77% picked this

  2. If the camera is working

    Bad Premise / Conclusion Match

    This does have three conditionals. But the two premises do not chain together (they both have the same outcome, "blurred"). One of the premises has an "or" in its trigger, but the "or" should be in the outcome. The conclusion has an "and" in its outcome, but it should be an "or". Any one of those observations could have been enough to disqualify this answer.

    9% picked this

  3. The photograph will either be

    Bad Evidence / Conclusion Match

    This does not have three conditionals, only two. The premises don't chain together (one of them is just a fact). Neither premise is a conditional with an "or" in the outcome. The conclusion doesn't have an "or" in the outcome. Any one of those observations could have been enough to disqualify this answer.

    5% picked this

  4. If the camera is working

    Bad Evidence / Conclusion Match

    This does have three conditionals. The premises do chain together. But ... Our second conditional premise has an "or" in the trigger, rather than the outcome. The conclusion doesn't have an "or" in the outcome. Either of those observations are enough to disqualify this answer. We were looking for this: Premise 1: A → B Premise 2: B → C or D Conclusion: ~C → ~A or D

    5% picked this

  5. The camera will work properly

    Bad Evidence / Conclusion Match

    This does have three conditionals. The premises do chain together. But ... Our second conditional premise has an "or" in the trigger, rather than the outcome. The conclusion also has an "or" in the trigger, rather than the outcome. Either of those observations are enough to disqualify this answer. We were looking for this: Premise 1: A → B Premise 2: B → C or D Conclusion: ~C → ~A or D

    4% picked this

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