September 2019 LSAT Section 1 Question 17

# Suppose the condition that only Zepi uses exactly one hyacinth and exactly one rose is replaced with the condition th...

Replies

Skylar on January 26, 2020

@Alexander-Blankers,For some reason, I am unable to see the game attached to your post. If you reply with the question number, the LSAT exam section or lesson section it is in, and a word or two about its topic, I should be able to find it and would be happy explain. Thanks!

Alexander on January 26, 2020

It's the September 2019 LSAT. The game regarding flowers.Skylar on January 26, 2020

@Alexander-Blankers, got it. Let's take a look at the game and see if we can make it any less intimidating.Here's our setup:

S: R R __ __

T: H G __ __

U: R H H __

W: G G __ __

Z: H R __ __

GHLR

Question #1:

We are tasked with determining an accurate list for U.

- Based on Rule 3, we know that U has R and H. We know that U must also have a second H because Rule 5 tells us that Z is the only one with exactly one R and exactly one H. Rule 3 says that U can has exactly one R, but at least one H, so H is the variable we choose to repeat. Therefore, we know that U = R H H and one other variable, so we are looking for the answer choice that is consistent with this setup.

- (D) is the only answer choice that includes R H H, so it is correct.

Question #2:

We are tasked with identifying a pair of people who could have matching arrangements.

- (A) is incorrect because Rule 1 tells us that S is the only person with two Rs.

- (B) is incorrect for the same reason that (A) is.

- (C) is correct. T and W could both have an arrangement of: H G G L without violating any rules.

- (D) is incorrect because we have already established that U = R R H, so it only has one open spot left. Rule 4 tell us that W already has G G in two of its four spots, so for these two people to match, their arrangements would need to be R R H G G, which requires more than four spots.

- (E) is incorrect because in order for W and Z to match, their arrangements would both have to be G G H R. This would violate Rule 5, which states that Z is the only person with exactly one H and exactly one R.

Question #3:

We are given a new restriction - that L is used by exactly two people, only one of whom also uses any H.

- From Rule 6, we already know that exactly one person uses two Ls. This means that one of the two people discussed in the question uses two Ls, while the other only uses one L.

- (A) is incorrect because S already uses two of the same flowers and we need a total of three types in each arrangement, so the two Ls must be assigned to U. However, we have already established that U only has one open spot left, so this is invalid.

- (B) is incorrect because both S and W are already assigned double variables. This means that neither could add two Ls to their arrangement and still have a total of three flower types in only four spots.

- (C) is correct. T could have H G L L while W has G G L R and no rules would be violated.

- (D) is incorrect because our setup requires that H is in both T and Z.

- (E) is incorrect because W already uses two of the same flowers and we need a total of three types in each arrangement, so the two Ls must be assigned to U. However, we have already established that U only has one open spot left, so this is invalid.

Hope this helps! I will post explanations for the remaining questions in this game shortly.

Alexander on January 27, 2020

Thank you! Your logic is crystal clear, and ultimately what I concluded. It just took me FOREVER to complete this game. I wasn't sure if there were any tips or tricks to parsing it out faster.Skylar on January 28, 2020

@Alexander-Blankers,Question #4:

We are asked to identify the answer choice that must always be true.

- (A) is incorrect because we can reference past hypotheticals to see that T has L L in (C) of #3 and L in (C) of #2

- (B) is correct. Rule 2 tells us that T has exactly one H and at least one G. We cannot add one R to complete this arrangement because Rule 5 states that only Z can have exactly one H and one R. We also cannot add two Rs because Rule 1 states that only S has two Rs. Therefore, T cannot use R.

- (C) is incorrect because we can create a hypothetical that places L in S without breaking any rules.

- (D) is incorrect because W has an H in (C) of #2

- (E) is incorrect because W has an R in (C) of #3

Question #5:

We are asked what must be true if we replace Rule 5 with the condition that Z AND at least one other person use exactly one hyacinth and exactly one rose.

- This would give Z and at least one other person the following arrangement: H R __ __. From the setup, we know that each arrangement must have exactly three types of flowers and therefore at least one pair. Since we can only have one H and one R here, this leaves G or L to be the pair in these arrangements. However, Rule 6 states that only one person uses two Ls. This means that Z could have H R L L, but the other person(s) would have to have H R G G. Therefore, at least one arrangement must contain no lilies, making (E) correct.

I'm glad you feel that the logic makes sense. Here are a few of the key things we did to save time while completing the game:

- We made the deduction that U has R H H __ early on.

- We relied on hypotheticals already constructed in previous questions to answer #4.

- We thought through #5 logically rather than creating individual scenarios to eliminate choices A-D.

Please let me know if you have any additional questions and best of luck with your studies!

Irina on January 31, 2020

@Alexander,This is a challenging game to visualize, and the key to it is to make as many inferences as possible for your initial setup. Overall, your game board should like a grid:

1 2 3 4

S

T

U

W

Z

The rules of this game are so restrictive that we can determine the possible combinations of flowers for every person. If you have made all the inferences, you setup should look like this:

S: R R H/L/G RRHL RRHG RRLG

T: HGL G/L HGGL HGLL

U: RHH G/L RHHG RHHL

W: GGL R/H GGLR GGLH

Z: HR G/L G/L HRGG HRLL

Note that only one out of T or Z can have two LL in their arrangement meaning:

If T: HGLL -> Z: HRGG

If Z: HRLL -> T: HGGL

If you have made all these inferences, going through the questions should not take you more than 3-4 minutes.

Let me know if you have any questions about any of the deductions.

Irina on January 31, 2020

https://imgur.com/a/tYNqi6w here is how it would look on paperHarrison on September 15, 2020

Question #5: If we are asked what must be true if we replace Rule 5 with the condition that Z AND at least one other person use exactly one hyacinth and exactly one rose. Why would the diagram below not work to counter the correct answer (At least one arrangement contains no lilies). I could have drawn more diagrams in which L was present in all conditions.S: R, R, H, L

T: H, G, R, L

U: H, R, L, L

W: G, G, R, L

Z: H, R, G, L

jing jing on November 4, 2020

Hi I am not an instructor but I believe your diagram would not counter the correct answer because it violates a rule in the stimulus which says that each person must use exactly 3 types of flowers. Your T has HGRL which is 4 types of flowers so that is why your diagram does not follow all the rules of the game.I hope that helps. Please feel free to correct me. Thank you

Abigail on March 9 at 10:24PM

Hi, why isn't c correct?S: RRG/H/L (FOR LAST TWO SLOTS)

T: LLHG

U: HHRG/L

W: GGHR

Z:GGHR

so, I chose C because exactly two of them have one rose and one hyacinth.

Emil on March 22 at 10:53PM

Hi Abigail, I think that it is not a scenario that must be true. We are looking for an answer that must be true, and while C could be true, it does not have to be the case.