37-3-3

tanes256

I'm stumped on 18. I set my diagram up to have my shelves numbered horizontically and JY sets his up vertically. I got all of the other questions right but I just couldn't figure out 18. Can it just be a coincidence that I got the other questions right and my diagram is just wrong for this passage? Or, am I just missing something in the way that I set up my diagram? My diagram is ok? I'm not getting "w" must be on the 3rd shelf with my diagram.

c.janson35

It's hard to say if your diagram is correct without seeing it, but odds are you are just missing something on 18 because it's really unlikely an invalid diagram would lead you to the correct answer on every other question.

There are only 2 places HP can be together: 2nd shelf and 3rd.

1: __
2: H P
3: F v/w ___

Or

1: __
2: F v/w
3: H P __

In each scenario, it cannot be the case that W is not in 3. Try to see if you can make it so it works otherwise.

If in the first scenario you tried to put W in 1 instead of 3 (because 2 is already full), you end up with a contradiction in 3 because V would be with S in 3.

If in the second scenario you chose W to go with F in 2, you would also be stuck in a contradiction because either V or S will have to be with P in 3, both of which aren't allowed.

tanes256

Ah! Got it! Thx @c.janson35!