LSAT 133 | Section 3 | Logical Reasoning: Q21

LR Question 21 Explanation

QUESTION TEXT: Chemist: The molecules of a certain weed-killer are…

QUESTION TYPE: Strengthen

CONCLUSION: Much of the data on the effects of the weed-killer are probably misleading.

REASONING: The effectiveness of the weed-killer depends on local soil conditions.

ANALYSIS: The stimulus doesn’t tell us anything about the data. If the studies accurately measure the soil conditions in the real world then they will be valuable. If they don’t measure conditions in the real world then they won’t be valuable. Simple as that.

Any answer choice that doesn’t mention data quality is wrong.

Don’t get distracted by the fancy language at the start. It’s just saying that the weed killer sometimes works and sometimes doesn’t. It can vary with soil conditions.

___________

1. This tells us absolutely nothing about data quality. The conclusion is only about data quality.
2. CORRECT. Bingo. Soil conditions in the real world generally don’t have the weed-killer molecules present in equal quantities. So the data is misleading.
3. This tells us that in most areas the weed-killer will be effective. But we don’t know if the research studies have taken this fact into account. So this doesn’t tell us if the research is useful or not.
4. This shows that the data is likely to represent real world conditions. It weakens the argument.
5. This is true. But it doesn’t tell us how much of the data makes this error. This answer choice leaves open the possibility that most data is accurate.