Why Answer Choice is E

It is possible to take statistics at 3 pm, then 9 am condition would not be apply. The only scenario when statistics must be taken at 9 am if one of the courses chosen is psychology, since it is not the case here, she could be taking the 3 pm statistics section.

How do we know that is the statistics at 3pm and not the one at 9am. Both rules 3 and 4 imply Stats9am. The answer choice, itself, does not address which stats is taken. This is confusing.

In addition, wouldn't it be more correct to say that since W - >NotS9am - >NoTP because we don't have statistics as a choice for answer choice C or D. Because if P is in, then statistics9am must be in per rule 4. Or can we just say that since P is in and no stats9am is in, on both C&D answers it violates rule 4, thus incorrect. For answer choice E: if W is in then stats9am is out, however, doesn't meant stats3pm is out, so we can still have a stats. Russian being in doesn't trigger anything so its fine. Thus Russian, stats and world history can be the three chosen.

@shenricus and @ulino23, happy to help. First, let's look at the game setup: G J M P R S(9)/S(3) WH __ __ __ __ | __ __ __ IN OUT Rule 1: Not R -> J Not J -> R So either J or R must be in, possibly both, Rule 2: M -> Not J J -> Not M So J and M cannot both be in. Rule 3: S(9) -> Not WH WH -> Not S(9) So WH and S(9) cannot both be in. Rule 4: P -> S(9) Not S(9) -> Not P Combining Rules 3 and 4 gives us: P -> S(9) -> Not WH WH -> Not S(9) -> Not P So WH and P cannot both be in. Rule 5: G or WH must be in, BNB Now, let's look at the answer choices: (A) is incorrect because it has both G and WH in, which violates Rule 5. (B) is incorrect because it has both J and M in, which violates Rule 2. (C) is incorrect because the combination of Rules 3 and 4 show that, since P is in, S(9) must also be in, and WH must be out. However, here both P and WH are in. (D) is incorrect for the same reason that (C) is incorrect. (E) is correct because R S(3) WH (J/M) is a valid possible group of courses Alicia could take. Note that Rules 3 and 4 only apply to S(9), not to S(3). In the scenario described in (E) the time of the statistics course is left open, meaning that we can pick whichever time works- which is S(3) in this case. Moreover in (E), Rule 5 tells us that we could not have G in, and the combination of Rules 3 and 4 show that we cannot have P in either. However, if either J or M fill the last "in" spot, the scenario is valid. Does that make sense? Please reach out with any additional questions!