# The student must take one or the other or both of

on December 8, 2019

How could we figure this out in a timely fashion without the hypotheticals?

Just out of curiousity...

Replies

Irina on December 8, 2019

@DrKumar,

One approach is to use scenarios from the prior questions for this game, which should allow you to reach the correct answer by elimination. Another approach is to consider the first rule by itself - if H is taken, then S & M are out, meaning we have to choose from the remaining 4 courses along with H - H + L P T W. Since there is no M, rule 2 is inapplicable, but rule 3 tells us that W & P are mutually exclusive, thus H's options are limited to the following combinations:

HLP
HPT
HTW
HLW
HLT

We do not actually have to write out this combinations, but can tell just by knowing that P & W are mutually exclusive that H must pick L or T or both to get to 3 courses. H is not a required class though, it is possible to have LTW or LTP combination that complies with all the rules, thus we can conclude that either L or T or both must be picked.

Generally, for a question like that I would look for one of the free variables because mutually exclusive variables often cancel each other out, and unless the rules tell us that if ~A then B - which indicates that one or both must be selected, it is possible that neither of them are selected - if A then ~ B.

on December 18, 2019

Thank you!

Ravi on January 14, 2020

@DrKumar, let us know if you have any other questions!