Q17 - On completing both the course

[eagerlawstudent]

I cannot understand why the answer is "E" and not "C". Please explain...

[ManhattanPrepLSAT2]

We are looking for an answer that MUST be true.

We are told that Angela will get her degree once she does 2 things --

Finishes course in experimental design & finishes course on dev. psychology.

We're also told she must take experimental design before dev. psychology.

Therefore, we know for CERTAIN that if Angela has finished dev. psychology, she must have already finished experimental design, and, since she's completed both, we can conclude she will indeed earn her degree.

Note that (C) does not HAVE to be true. One way to think of whether an answer HAS to be true is to consider the alternative. The alternative for (C) would be that there ARE prerequisites for experimental design. Would that conflict with the argument? Not at all -- Angela would still need AT LEAST 2 terms to graduate (if C were true, she'd likely need more than 2). Therefore, (C) is not something that must be true.

If that got you turned around, here's a simpler argument to illustrate:

Jan wants to pack a box and toy in her suitcase. The box weighs three pounds. Therefore, the suitcase will weigh at least three pounds --

Note, we don't know, and don't need to know, anything about the weight of the toy based on this conclusion.

Similarly, since we already have all the reasoning we need to show why Angela would need at least two terms, we don't know for sure anything about the requirements (or lack thereof) for the experimental design course.

Hope that helps! Please follow up if you need further clarification.

[bbirdwell]

It's important to have the correct task in mind when you do a problem like this. Forget assumptions and gaps and don't get drawn into the trap of evaluating the reasoning too much -- the correct answer MUST be true, provable, so simply note the facts:

1. When she finishes both Design and Development, she's earned her degree.

2. Design must be completed before Development.

3. Design is not offered until next term.

4. At least two terms before she gets her degree.

(C) could be true. it could not be true. We simply don't know whether or not that class has pre-reqs. Maybe it doesn't. Maybe it does, and she took them three years ago.

(E) must be true. Simply read facts 1 and 2 above. When she finishes those two courses, she gets the degree. And she's got to take one of them before the other. Therefore, when she completes the second one, she gets the degree.

See what I mean?

[sbuzzetto10]

I understand why "E" must be correct, but what I don't understand is why the correct answer choice is saying almost exactly what the first statement of the passage says. When doing must be true deduction/inference questions, I'm so used to having to figure something out based on relating/connecting information in the passage that it seems like obvious answers like "E" on this one are a trick. Is this common?

[bbirdwell]

First of all, the correct choice here does not say exactly the same thing as the first sentence -- you do have to put two things together to arrive at the correct answer (re-read previous post).

If I told you, "After I drink a Corona and a Newcastle I'll be done for the night." You would not automatically conclude answer choice (E), "When I finish the Corona, I'm done." You need another piece of information, "I've already finished the Newcastle."

That said, I understand your feeling that this answer was somewhat "obvious," and I would say this is often the case on these questions. Consider a spectrum. On the left end of the spectrum is "pretty much written on the page," and on the right end of the spectrum is "add together a bunch of complex information and arrive at a startling and brilliant new insight."

Answers to inference questions are always much closer to the left.

[nlynes]

What about answer choice D? Is it because there are different kinds of psychology degrees? I understand why E but D also seemed like a possible answer.

Thank you

[timmydoeslsat]

Answer choice D is flipping the suff/necessary conditions.

We know that she is this:

ED and DP ---> a Degree in Psych

But we do not know that these 2 classes are necessary for earning a degree in psych.

There can be an array of classes that one can take to achieve the hours required for the degree. She simply could have chosen to take those 2 classes rather than the 100s of others that were available.

[AndyC64]

Why B is wrong?

Since before taking developmental psychology, experimental design must be completed. In other words, experimental design must be an earlier course than developmental psychology course.

Is there anything wrong with this line of thinking?

Thanks!

[AbhishekM843]

Why B is wrong?

Since before taking developmental psychology, experimental design must be completed. In other words, experimental design must be an earlier course than developmental psychology course.

This isn't necessarily true. Perhaps the professor that teaches experimental design gives harder tests than the professor that teaches developmental psychology. Also, notice how no where in the stimulus does it talk about how easy or hard the classes are. So, this line of thinking would be out of scope.