Q22

 
JasonS552
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Vinny Gambini
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Q22

by JasonS552 Tue Apr 02, 2019 9:13 am

Could someone please help with this question?
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ohthatpatrick
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Re: Q22

by ohthatpatrick Tue Apr 02, 2019 6:42 pm

A "fully determined" / "completely determined" question is what I like to call the 'Magic Domino' question type.
1 correct answer triggers a series of chain reactions that lock everyone into place.
4 wrong answers leave the situation at least somewhat flexible.

IDEAL WORLD STRATEGY:
we find an answer that pins down a floater or that decisively activates a couple rules.

OFTEN-TIMES REAL WORLD STRATEGY:
just start pluggin' and chuggin'

In this game, there are no floaters.

There are a couple toss-ups that would be great to know
- which person is giving it to R and S?
- Is it R or T giving to Q?
- It is T or U giving to P?

It seems like T and R would be the most important ones in that equation.

A) If R gives to Q, we still don't know whether T or U gives to P, or who gives it to R and S.

B) If T gives to Q, then U gives to P.
Who is left to give it to R and S?
Can't be T or U, since you can't give it to three things.
Can't be R or S, since you can't give it to yourself.
It would have to be P or Q.

More than one possibility.
T -> Q -> (R) and (S --> U --> P)
U -> P -> (R) and (S --> T --> Q)

C) If T gives to S, we know who gives to R and S.
We know that R gives to Q
We know that U gives to P

This was more powerful than (A) or (B), neither of which settled all three issues.

T --> (R --> Q) and (S --> __ )

U gives to P, so how do we get that on there? Well, since S needs to give to SOMEBODY, it would have to be S --> U --> P

T --> (R --> Q) and (S --> U --> P)

This settled everything, so it's the correct answer.


D) This doesn't settle whether R or T gives to Q, nor does it tell us who gives to R and S.


E) This tells us that T gives to P, and that U gives to R and S, but it doesn't actually tell us whether T or R gives to Q. Super sneaky. T could still give to two things.

It could be R --> Q like this
U --> (R --> Q) and (S --> T --> P)

or it could be that T --> P and Q like this
U --> (R) and (S --> T --> P and Q)


Ouch, that was brutal. I can't believe no one had asked about this one yet.
Hope this helps.