Setup and Rule Diagrams

[ekangela]

Hi!

I have a question about an inference that I made when setting up the diagram for this game. I'm not sure if this has been discussed elsewhere (I checked the discussion on every question for this game and couldn't find anything), so sorry if I'm asking a question already answered!

While making inferences with the rules, I got to the inference of NR or UR -> not NP alright, and from there, I got NR or UR -> not NP -> NJ or UJ. This reduced is NR or UR -> NJ or UJ. But the contrapositive of the third rule shows NR or UR -> not NJ or not UJ, which would contradict the earlier inference... So is it correct to assume then that neither NR nor UR will be on sale?

Thank you,
Angela

[Adam Tyson]

Good question, Angela, and you are right on the cusp of the right inference there! If any Rap is on sale, you must have SOME Jazz on sale, but you cannot have BOTH Jazz on sale. That means you can have Rap, but then you have to have exactly one type of Jazz! Not both, and not neither, but exactly one!

[christinecwt]

Hi Team,

May I know for Rule #4, why the "separate music type representation" referring to "NP" while "subscript music type designator representation" refering to "P" instead? Isn't the "subscript music type designator representation" wrong as it includes both New Pop and Old Pop.

Thanks!

[Dave Killoran]

Hi Team,

May I know for Rule #4, why the "separate music type representation" referring to "NP" while "subscript music type designator representation" refering to "P" instead? Isn't the "subscript music type designator representation" wrong as it includes both New Pop and Old Pop.

Thanks!

No, it is correct. What I did there is combine known info with the rule. We know from the very first rule that "Used pop is on sale; new opera is not."

So, when the fourth rule states that, "If neither type of jazz is on sale, then new pop is," it actually means both Pop types are on sale since we already know Used Pop is always on sale. This makes it even easier to connect with the second rule then.

Thanks!