June 2019 LSAT
Section 4
Question 20

# If Pang works on only one day, which one of the following must be true?

Replies

BenMingov on June 20, 2020

Hi Maria-Marin, thanks for the question.With P going once, all other variables must occur twice.

Answer choice D is incorrect because Pang could be placed Thursday without issue. You can try filling that out. Notice that this doesn't lead to any rule violations.

On the other hand, answer choice B. If we didn't have M in Saturday, then we would have M in Thursday and Friday. This would use all of our M's and L's (because L is necessary for M). Since P can never go Saturday, the only two variables left to fill Saturday are N and Q. This isn't enough.

I hope this helps. Please let me know if you have any other questions!

on September 10, 2021

How is Q not required to go on saturday? I understand why B is correct, but I do not understand how E is wrong. If someone could explain it to me, I would appreciate itRita on January 10, 2022

^^^ I have the same question. If P and N are both eliminated that leaves M, L, and Q. But what makes M a better choice than Q to have to be on Saturday?Ravi on February 8, 2022

@Rita, looking at the scenarios, you could have one scenario where P works on Friday with N and Q.In the original deductions of the game, we know that N must go on Friday and L must go on Saturday.

As Ben said, all the other pieces have to show up twice is P is just working once. L would be working on Thursday and Saturday, and M will also have to be on Thursday and Saturday since Friday is full. The last two spots on Thursday and Saturday can switch between N and Q. In the second scenario, you could put P on Thursday. M has to go where L is since they're both going twice and if you have an M, you have an L. Thus, we also know that when P goes on Thursday, M will also be going on Saturday, just as it did in the scenario where P was only going on Friday. That's how we can pick B as the correct answer.

christophergogo on June 3, 2022

Still not making sense.Senario 1

T: P N Q

F: N M L

S: M L Q

Senario 2

T: M L (Q/N)

F: N P (N/Q)

S: M L Q

As you can see, Q must be on Saturday. Also, M must be on Saturday. This makes both answer choice D and B correct. Can an instructor explain this apparent paradox?

christophergogo on June 3, 2022

I see it now. Senario 2 is false because you can't have N twice. It should be:Senario 2

T: M N (Q/N)

F: N P Q

S: M L (N/Q)

The common denominator of both scenarios is that M *has* to be on Saturday. However, Q *does not have* to be Saturday.

christophergogo on June 3, 2022

Sorry, correction:Senario 2

T: M L (Q/N)

F: N P Q

S: M L (N/Q)