Logic Challenge #33 - A Fishy Game (Hard)

[noah]

How did you solve this beast? Best explanation wins a prize..

[rpcuhk]

Hi, I e-mailed my explanation to you.

[Noah: I loaded it for you!]

fish game explanation by rpcuhk.pdf

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[TIDEDRAGON]

I started by graphing three Venn circles that did not intersect, placing each pair of fish in a globe label with their place of origin. In the California circle, I wrote "farm," since both of the CA fish were farm-raised. In the Alaska circle, I wrote "1 wild." Then I drew two boxes, one containing two F's (farm) and the other with two A's (Alaska). I struck a line through both boxes to denote "not paired."

Now I drew my number line - six blanks. Under the second space (Tues) I wrote "H/JD." Under Thursday, OR/P. Then I began answering questions.

Q1. Tuesday had to have either Halibut or John Dory, so A and B were out. OR/P on Thursday eliminated D. And two Alaskans could not be paired, so E was out. C fits the parameters.

Q2. B/c farmed raised cannot be paired, and with the restriction of Tues & Thurs being East Coast and Alaska, along with both California fish being farmed-raised, 3 farmed fish must fall on Monday, Wednesday, and either Friday or Saturday.
D and E could be true, but the question ask MUST, so they are out. A and B, same issue; could be. C must be true to satisfy the pattern.

Q3. From Question 2, we already know that A and B are true. And we know we can't fit four farm-raised fish on the board, so D and E are true. The only NOT TRUE is C. It could be true, but it is not a MUST be true.

Q4. "Could be false" questions mess me up, so I slowed down for this one. I focused on defining each item as "true." A is true b/c no R+S together. Back to Q2 seems to prove B - Sardines could Monday or Wednesday. This is the distractor. If they are Monday, that leaves only Wed & Fri blank, violating the A-paired rule. B is true. We know that Sardines reside on Wed, so the Tuesday fish must be wild, making C and D true. That leaves E. If pomfret is farmed-raised, it could fall on Monday. So it could be false.

Q5. It cannot fall on Tuesday b/c that's reserved for East Coasters. Wed + Fri conflicts with the no A+A, and Thursday must be included as an option, as well as Monday - just proved so in Q4. Nothing prevents it from falling on Saturday as well. I didn't bother eliminating answers in this question b/c my answer matched E.

Q6. Question 2's proof helps here again. We know the possible pattern for farmed fish must include a Mon or Wed. "Must be farmed raised" is a bogus restriction, blocking A & B. Monday and Saturday can offer fished both farm raised or wild, and from Alaska or California. D & E, out. If both East Coasters are farmed, they block Mon & Wed, which are required for a California fish. C is the answer.

Hope this helps.

CP

[LGLEGLI]

I looked at it as a simple graphing project:

As such, I assigned each fish a respective number 1-6 along the left side and the days of the week 1-6 across the top.

Then, for the specifics, like regions..E=East coast, C=Calif, A=Alk. Next, I labeled each as WC=wild caught or FR=farm raised and then just filled in the grid with the possibilities.

And, if I didn't have such a massive headache from work today, I'm sure I would have done better.
thanks,

Karen

[newavonhotel2]

oh my god my head is aching for that logic. lol

[samantha.b233]

Here is my try.

https://docs.google.com/document/d/1nZm ... LjuFk/edit

[ohthatpatrick]

WOW! That is some really interesting and innovative work there.

Is this how you did the game the first time you tried it or how you thought through the possibilities upon further reflection?

If the former, how long did it take you to do the game this way?

The problem with the time constraint on the Games section is that we often don't have the time or workspace to conduct such a thorough analytical assessment of the game.

Essentially, you took a combinatorics type approach in casting a wide net for all the numerical possibilities and then pruned away the ones that violated rules.

In a timed setting, it's probably more realistic that we'll have to just exclude some possibilities that CAN'T be true without necessarily working through all the ones that COULD be true.

This is a weird sweet spot to find: essentially we often have to do a Game with a fair amount of uncertainty because we don't have time to conduct an exhaustive investigation of the game before going to questions.

Anyway, as an exercise in analytics, you crushed this!

As a realistic way to do this game in under 10 minutes, this might not work for everyone.

Thanks!

[samantha.b233]

In reality, though, I would probably use a more "ordinary" approach. But this is definitely a good game to practice with. I was hoping by practicing with enough games like this, I can eventually solve problems at a good speed.

As an aside, this type of game, if it does appear in the real LSAT, you are probably expect to take more than 8 minutes to get through anyways.

[clark5901]

Thanks for the nice information in this post dear...