If W precedes Y on the CD, then which one of the following must be true?

Marissa on July 19 at 09:37PM

New vs Rock

Im a little bit confused. How is it that T is for sure a New song, but S is not rock since it immediately precedes Z, a rock song?

1 Reply

Irina on July 19 at 10:48PM

@Marissa,

Let's look at the setup for this game:

It is a hybrid game, where we have to determine the order as well as classify the songs into [R]ock or [N]ew.

(1) S occupies the 4th track

S
_ _ _ _ _ _ _
1 2 3 4 5 6 7

(2) Both W & Y precede S

W < S
Y < S

S
_ _ _ _ _ _ _
1 2 3 4 5 6 7
~W ~W ~W
~Y ~Y ~Y

(3) T precedes W

T
then

T
S
_ _ _ _ _ _ _
1 2 3 4 5 6 7
~T ~W ~W ~W
~Y ~Y ~Y
~T ~T ~T

(4) A rock classic occupies the 6th track
R
S
_ _ _ _ _ _ _
1 2 3 4 5 6 7
~T ~W ~W ~W
~Y ~Y ~Y
~T ~T ~T

(5) Each rock classic is immediately preceded on the new CD by a new composition

NR

N N R N
S
_ _ _ _ _ _ _
1 2 3 4 5 6 7
~T ~W ~W ~W
~Y ~Y ~Y
~T ~T ~T

This rule tells us that #1, #5 and #7 must be New Composition.

(6) Z is a rock classic.

Since, we do not know the exact position of Z, I am not going to put this rule on the diagram just yet, but let's keep it in mind when we get to the question.

Now, the question says if W precedes Y, which of the following must be true?

This rule allows us to determine the order of the first 4 songs:

T
We also know that Z must be #6 because it is a Rock song, and #5 and #7 are New Compositions. We can then conclude that X & V must be either #5 and #7 or #7 and #5 and are both New Compositions. We can finally conclude that T is a New Composition because it is #1.

N N R N
T W Y S Z
_ _ _ _ _ _ _
1 2 3 4 5 6 7
~T ~W ~W ~W
~Y ~Y ~Y
~T ~T ~T
/X /V
/V /X


As we can see from the setup, S is #4 and Z is #6, it does not immediately precede Z.

Let me know if this helps and if you have any other questions.