PrepTest 113, Section 2, Question 25
In a car accident, air bags greatly reduce(40 more words not shown)
The argument is most vulnerable(7 more words not shown)
- Aassumes, without providing(14 more words not shown)
- Bdenies the possibility(24 more words not shown)
- Coverlooks the possibility(14 more words not shown)
- Dassumes, without providing(26 more words not shown)
- Etakes for granted(10 more words not shown)
Reading the argument
How much does each difference matter?
The two facts pull in opposite directions. Cars with air bags are more likely to be involved in an accident, but the air bags greatly reduce the risk of serious injury in a crash. The author treats the first difference as enough to cancel the second. We haven't been given the sizes of those effects.
Imagine a 90 percent reduction in the chance of serious injury during an accident, alongside only a 1 percent increase in the chance of an accident. Those are illustrative figures, not the study's results. But they show why a small increase in crashes could be outweighed by a large reduction in serious injuries. Merely knowing that one measure goes up and the other goes down doesn't establish the overall result.
What we’re looking for
For the flaw question, I'd look for that unsupported weighing of the two considerations. We don't need to explain why the cars have different accident rates. We need to ask whether those rates establish that the cars with air bags are no safer.
Working the answers
- A
More likely doesn't mean likely to happen. One car could have a very small chance of an accident and another could have a slightly larger, still very small chance. The argument doesn't need to assume that a car with air bags will probably crash. Its mistake concerns how the higher chance affects the comparison of safety.
- B
Other safety features on cars without air bags could help the author's position. If those features reduced serious injury just as effectively, that could supply a reason to doubt an overall safety advantage for cars with air bags. The author hasn't denied that possibility, and overlooking it wouldn't explain the unsupported dismissal of the air bags' benefit.
- C
The two kinds of car can be involved in the same collision. That doesn't settle their occupants' risks of serious injury, and it doesn't tell us how to weigh the overall accident rates against the protection air bags offer. C points to a possible shared accident without addressing the disputed comparison.
- DCorrect
The author lets accident likelihood outweigh, or at least offset, the reduction in serious injury. But why should that be the controlling consideration? If the protection from serious injury is large enough relative to the increase in accident risk, the cars with air bags could still be safer overall.
D identifies the assumption behind the conclusion that they are no safer. The argument gives us the direction of two effects and proceeds as though it knows their relative importance. Our example shows why we need more than those directions to make that judgment.
- E
The argument doesn't require every accident to deploy an air bag. Air bags could greatly reduce the risk of serious injury across accidents without activating in every minor collision. The given benefit and the higher accident rate would still leave the same question about overall safety. Deployment in every crash isn't the missing assumption.
More Flaw questions
Learn the LSAT our way
Our platform drills Flaw questions at your level and adjusts as you improve.