Q19

[chungyesol]

I got other questions right in the section, but I am having a problem with #19. I don't even understand what the questions is asking, so could you please clarify here what the question is asking and why the answer is K,Q? Is the question asking we need to pick one that has at least one rep from the pair fits into every situation? Help, please.

[timmydoeslsat]

This is a global question asking us which one of the following pairs of people must have at least one in? In other words, which pair of people is it impossible to have both be out.

When I look at this question, I was wanting something that would lead to drastic measures. I knew from looking at the rules that a possible answer would be to have J or M along with K...as this would force out 4 Ts, leaving only 1 T, which is a rule violation due to the fact that we must always have at least two from each side.

I then considered the answer choices that would force things out, so I was attracted to the answer choices that contained necessary conditions, in particular C.

F ---> Q

G ---> K

To have both Q and K out will lead to both F and G being out. This would fill up the out column and would force both M and P to be in, which is a rule violation.

Previous use of your hypothetical work during the game would help with this question to in regards to eliminating answer choices where both members of the pair were out and it was a valid scenario.

[ohthatpatrick]

Nice explanation.

I'll just add a sample scenario to disprove each of the wrong answers for those who were tempted by anything else.

A) In: J M K Q R Out: F G P S
B) In: F K Q R S Out: G J M P
D) In: Q R S F K Out: M P J G
E) In: F G K P Q Out: R S J M

[alex.cheng.2012]

Just wanted to add something. If you framed this, you would have seen Q popping up quite often. That would have been an indicator to try answer C first. If you didn't frame it, you could still look back on your previous work (just a quick glance, but questions 12, 14, 15, 17) you'll see Q pop up quite often as well. That should also give you heads up to try out answer C first.