Logical reasoning PrepTest 140 · Section 3 · Question 7

Correct. Argument or Facts:
Argument

Valid or Flawed:
Flawed

Question Type:
Errors in Reasoning

Stimulus Summary:
There are more injuries at well-marked crosswalks than crosswalks not well marked, so these markings don't work.

Answer Anticipation:
This argument falls into a common pattern, generally highlighted by a conclusion that the argument treats as establishing that a certain feature isn't working. Here, the striping and flashing lights are meant to enhance safety, but the crosswalks with them have more injuries; the argument then concludes the safety features don't work.

However, the relevant comparison is between the same crosswalk before and after the safety features, not between crosswalks with these features and without. We don't know that the crosswalks are otherwise relevantly similar. It's possible that the area with the additional features is more dangerous than others, which is why those features were installed in the first place. The correct answer should highlight this potential difference between the crosswalks.

Answer Explanation:
This answer highlights the possible difference in overall danger presented by the areas with the crosswalks. If the ones with the additional safety features are just inherently more dangerous, then it's possible the safety features are lowering the injury rate below what it would be without them even if that rate is higher than safer areas.

Key Takeaway:
This argument falls into a common pattern. A solution is presented, but the problem it's trying to solve persists to a higher level than in other areas, so the solution is determined not to work. In these cases, the correct answer almost always highlights that the area where the solution was implemented had a larger problem to begin with, highlighting a relevant difference between the areas that explains the higher level of problem while still allowing the solution to work.

Incorrect. The argument doesn't establish or treat the safety features as if they fail to reduce the number of injuries—just that they don't do so at a level that makes it worthwhile. The author could believe that a few injuries are avoided, but, based on the higher overall injury rate, it's a waste of taxpayer money to implement these features.

Incorrect. The conclusion doesn't relate the cost of these safety features to others—it just states that the current safety features are a waste of money. The author doesn't need to assume there's a better use of money to conclude that something is a waste of money.

Incorrect. If anything, the argument would consider more features at these injury-prone crosswalks to highlight that all of these safety features are a waste of money.

Incorrect. Who gets most injured in an accident doesn't speak to the efficacy of safety features.