Logical reasoning PrepTest 102 · Section 2 · Question 15

Incorrect. This answer limits when the situation in question may have happened, but it doesn't change any of the details that would lead us to expect it to be at a specific temperature range.

Incorrect. What matters is the temperature, not how comfortable people would be in that temperature.

Incorrect. This doesn't speak to the temperature in this specific situation, so it's out of scope

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Weaken

Stimulus Summary:
Rhododendron - Leaves curl when temperatures are below 0C
Crocus - Blossoms open above 2C
Someone has:
(1) A rhododendron with uncurled leaves
(2) A crocus with unopened mature blossoms
(3) A thermometer showing 1C
Conclusion - The thermometer is accurate to within 1 degree.

Answer Anticipation:
This conclusion is led into with three pieces, so let's tackle them piece by piece.

The first piece establishes there's a rhododendron with uncurled leaves. According to a premise, the leaves curl below 0C, so this establishes that the rhododendron is at 0C or above.

The second piece establishes there's a crocus with unopened mature blossoms. Those blossoms up above 2C, so this establishes that the crocus is at 2C or below.

Finally, we have the thermometer which states that the temperature is 1C.

The conclusion is that the thermometer which states the temperature is 1C is accurate to within 1C. The rhododendron suggests that the temperature is at least 0C, and the crocus suggests that it's at most 2C, which seems to back this up.

It's hard to see, therefore, what the flaw is in this argument that suggests the thermometer might be off by more than 1C. Since this argument feels valid, we must be missing something—so let's head into the answers, staying flexible so we can figure out what it is.

Answer Explanation:
This answer establishes that the temperature experienced by a rhododendron and a crocus close to each other can differ quite a bit. This means that even though we can tell from the stimulus that the rhododendron in question is at at least 0C and the crocus is at at most 2C, the surrounding air could be a very different temperature than at least one of these plants, and thus the thermometer could be off by more than 1C. This answer weakens the argument and so is correct.

Key Takeaway:
This was a tough question! The stimulus appeared to present a valid argument, but we know that can't be the case in a Weaken question, since we weaken argument by calling an assumption into question. When this happens, head into the answers with some flexibility, knowing that you're missing some context that would call the relevance of the premises to the conclusion into question.

Incorrect. First, there's no indication that the thermometer in question falls into this category. Second, there's no indication what range of temperatures counts as "extremely accurate" and "much less accurate," making it hard to know if being off by a degree falls into either of those categories.