PrepTest 101, Section 2, Question 11
Not surprisingly, there are no professors under the(30 more words not shown)
If the statements above are(16 more words not shown)
- ANo professors are(1 more words not shown)
- BAll brilliant people(8 more words not shown)
- CSome legal voters(3 more words not shown)
- DSome professors are(6 more words not shown)
- ESome brilliant people(6 more words not shown)
Reading the argument
Being brilliant doesn't let someone skip the age restriction. Pick one of the brilliant people who is under eighteen. Under the facts we're given, that person cannot legally vote and cannot be a professor. We already have a useful connection: some brilliant people are outside both of those groups.
The other statements don't change that. Some brilliant people are professors, and some are legal voters. That tells us those groups contain brilliant people; it doesn't tell us that every brilliant person belongs to one of them. It also doesn't tell us how the professors and legal voters overlap with each other.
What we’re looking for
We're asked what must be true based on these statements. So keep our brilliant person under eighteen in view. “Some brilliant people cannot vote” would work, and we can say more: those same people cannot be professors either. The answers may offer things that sound obvious in real life, but the right answer needs support from these particular facts.
Working the answers
- A
Under eighteen isn't the same as eighteen. The passage rules out a seventeen-year-old professor, but says nothing that prevents someone from being a professor on their eighteenth birthday. We don't need to know whether that happens in real life. The given rule simply doesn't cover eighteen-year-olds.
- B
The passage gives us some brilliant people in each of these categories, not a complete list of where all brilliant people can be found. Imagine a brilliant twenty-seven-year-old who isn't a professor and isn't legally eligible to vote. That person would fall outside all three categories, without contradicting any of the statements. B rules out a possibility the passage leaves open.
- C
This sounds familiar from everyday life: plenty of people can vote without being professors. But where do the stated facts establish that? They don't tell us that even one legal voter is outside the professors group.
As far as these statements go, every legal voter could be a professor. There could still be brilliant people in that overlapping group and brilliant children outside it. The facts would all remain true while C would be false. Our knowledge of actual voters can't fill that gap in a must-be-true question.
- D
We aren't given a professor who lacks either of these features, much less both. All professors could be brilliant legal voters without violating the passage. Saying some brilliant people are professors doesn't mean other professors must be unbrilliant. “Some” establishes an overlap; it doesn't impose a limit on it.
- ECorrect
We know some brilliant people are under eighteen. Every person under eighteen is excluded from being a professor and from voting legally. Therefore those brilliant people are neither professors nor legal voters.
Notice that both exclusions apply to the same people. We aren't taking one brilliant person who can't vote and a different brilliant person who isn't a professor. The under-eighteen group gives us people for whom both things are established. That's direct support the more familiar-sounding C lacks.
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