Logical reasoning PrepTest 129 · Section 3 · Question 23

Incorrect. While the brushes were tougher on finishes, the older cars were more resistant to scratches. It's impossible to know whether, on balance, the tougher brushes scratched the tougher finishes more than the softer mitters scratch the more easily scratched finishes. Additionally, we don't know how many cars are on the road today versus the old days, and how those cars are split between the cars with the new finishes and the old ones!

Incorrect. There's no indication as to why mitters replaced brushes, so we can't infer causality.

Correct. Argument or Facts:
Facts

Question Type:
Must Be True

Stimulus Summary:
Mitters are easier on finishes than brushes.
New cars are more easily scratched than older cars.

Answer Anticipation:
This stimulus is all about the comparisons—it compares mitters to brushes, and new car finishes to old ones. Both comparisons deal with finishes, so the two are connected and will probably be combined in some way to create an inference. For instance, since mitters are easier on finishes than brushes, and old cars are more resistant to scratches than new cars, then it's likely that mitters don't scratch old cars all that much.

Answer Explanation:
This answer definitely doesn't have to be true, but it's the most supported of the lot. If mitters are gentler on finishes than brushes, and old finishes are more resistant to scratches than new finishes, then it's very likely that the new, softer mitters don't visibly scratch the old, more scratch resistant finishes. After all, if car washes are generally visibly scratching finishes, then they probably wouldn't get much business!

Key Takeaway:
Most Must Be True questions that ask you to find an answer that's "most strongly supported" have answers that are almost certainly true. This is a rare exception where the correct answer really is just the most supported one. Don't see this as a common trend, but instead use it to allow yourself to pick an answer and move on on one of these questions when you've eliminated four answers but don't feel 100% on the remaining one.

Incorrect. The stimulus doesn't discuss effectiveness, so this answer is out of scope.

Incorrect. The stimulus notes that "many" cars made today have clear-coat finishes, so there's no basis to conclude that they make up a larger group than cars with older finishes—the new clear-coat finishes may only have been implemented a year or two ago.