Q14

[ShehryarB30]

Could you pls explain this

[ohthatpatrick]

I would hold-off on doing Q14 until I had done all my "If" questions.

Q15 gave us this scenario
S S [] M M M [] S S

Q16 gave us this one
S S S [] M M M [] S

Q17 gave us this one
M M [] S S [] M [] S

Let's look at the answers for Q14 and see if we have any counterexamples:
(A) Q17 says otherwise
(B) Keep it
(C) Q16 says otherwise
(D) Keep it
(E) Q15 and Q17 say otherwise

Down to (B) and (D), we'll ask ourselves
(B) "Can we make 1 and 2 a mix of M and S?"
(D) "Can we keep all three M's apart?"

We should already know the answer to (D) by this point, because when we worked on Q13's (A), we realized that if you separate all the M's, you have WAY too many cleanings:
M [] S [] M [] S [] M [] S S

So (D) is the correct answer, because we must always have at least two M's together. We can't do otherwise.

If we were trying to prove (B) wrong, it would look like this
M [] S S S [] M M [] S

[ShariS937]

I think the MP explanation is meant to be in a different thread?

I could only brute force this one and am generally confused by In/Out games...but:

Q: How can we avoid assigning S3 or S9, either In or Out?

The question asks for a scenario where Alicia can take either S3 or S9; since she can't take both S3 and S9, putting either one In forces the other Out.

So, I think we're looking for a pair that brings in exactly one more element and leaves a slot open for S3 or S9 (to meet the four classes total requirement).

GJ | forces out WMR - ok so far, defer
GP | forces S9 in, eliminate
JW | forces S9 out, eliminate
PR | forces S9 in, eliminate
RW | forces S9 out, eliminate

If I'm thinking about this the right way, maybe a simpler approach would be:
- Any choice with P in forces S9 in and S3 out
- Any choice with W in forces S9 out and S3 in
- That does actually just leave A! Which is correct.

[Laura Damone]

Great reply, and you're totally right!

You can work wrong-to-right here without doing any prework, or you can look at what would trigger a guaranteed In or Out placement of S3 or S9 and eliminate any answer that contains a triggering element.

It's also fine to dig into A right away, drawing a T chart. I'd start with GJ in, which kicks W and M out. Then I'd do an S3 /S9 cloud over both groups, and see who's left. That leaves only R and P. If P went in, it would force S9, and that's not allowed, so I place P out. R, then, goes in. That's a valid diagram, so you can select it without checking the other choices if you want to!

Nice work!