#22 - Local

[Administrator]

Please post your questions below!

[AnaSol]

Hi,

When I was solving the game I saw right away that the block KG had to go on Su, Mon and Sat so that N and H could be separated.

Answer choices A and D describe this. What makes D superior? Why A doesn't work? If G is on Mon, then K has to be Sunday and consequently Saturday. What am I missing?

Thanks!

[Luke Haqq]

Hi AnaSol!

To address answer choice (D), if L is assigned to Thursday, that adds a constraint as to where G can go. We already know that G can't be on Saturday or Sunday, since G only occurs once and the Sat/Sun variable occurs twice. We also know that G can't go on Wednesday, because there'd be no room for K to come before or after it.

That leaves Friday as one possibility for G, which would mean that K goes on Saturday, in which case K would also be on Sunday. Another possibility is for G to be on Monday, in which case K would be on Sunday. So there are only two possible places where G could go based on the local restriction in this question, and in either case that results in K being on Sunday.

Regarding answer choice (A), that could be true. G could be assigned to Monday. But as discussed above, it's also possible that G could be on Friday. Answer choice (A) is incorrect because this question asks for what must be true rather than could be true.