#5 - Local, Must Be True

[Dave Killoran]

Complete Question Explanation

The correct answer choice is (B)

If O is seated next to X, then from a row assignment standpoint we have the following:

• Front row: N
  Middle row: R, P, X
  Last row: O, X

Thus, S, T, and U remain to be assigned to row, and two of those travelers must be assigned to the front row and the other traveler must be assigned to the last row. From the effects of the last rule, we can deduce that both S and U cannot be assigned to the front row. Thus, one of S and U is assigned to the last row, and the remainder of S and U is assigned to the front row, along with T:

• Front row: N, T, S/U
  Middle row: R, P, X
  Last row: O, X, U/S

From the last rule, we know that neither S nor U can be assigned to a seat immediately beside N, and so in the front row T must be assigned to seat 2 (T in the middle seat separates N from the S/U option). Accordingly, answer choice (B) is correct.

[StudyEveryday]

Hi! I am a little confused about this one because I thought that "Only seats in the same row as each other are immediately
beside each other", so wouldn't that mean U/S and O would have to be next to each other, so the unassigned seat cannot be in the middle?

Wouldn't it be something like this:

U/S, O, /

or

/, O, U/S

Thank you!

[Rachael Wilkenfeld]

Hi Study,

I think you have the rule backwards. It's not that all seats in the same row are next to each other. It's that only seats in the same row are next to each other. That means that there can be seats in a row that are not next to each other, and the empty seat can be in the middle.

If we were to diagram our rule conditionally, it would look like this

Seats next to each other seats in same row.

Hope that helps!
Rachael

[oatmilkexpert]

Hi! Why is (C) incorrect? Is it because U and S can interchange between the first and last rows and therefore U does not need to be in Seat 1?

[Robert Carroll]

oat,

That's true, U doesn't have to be in seat 1, in part because U could be in the last row, and thus not even in the same row as seat 1. But note also that it's possible for U to be in seat 3, which is another reason U doesn't have to be in seat 1.

Robert Carroll

[oatmilkexpert]

Thank you so much! Your explanation was super helpful.