If one of the rules clearly states if a recycle center is recycling wood, newsprint must be recycle at the same place, how come C is not the correct answer?

Hi Ielisa,

Let's start with what we know.

We know that W is in C1, and C1 is the only Center with W. (Stem Rule)

We also know that W → N. So C1 must have W + N.

Now, recall that C2 must have at least two items, and that C1 can have at most three items.
Since ALL items recycled in C2 must also be recycled in C1, we can infer that N must be recycled in C2.
(This must be true because the other item in C1, Wood, can ONLY be recycled in C1, and there can be AT MOST one item in C1 that is not also in C2.)

So now we know the following:
C1: N, W
C2: N
C3:

Another thing we know is that the 2nd item at C2 cannot be P (because P can only be recycled x1). And we also know that P cannot be at C1, because C1 already has one item NOT in C2 (that item is W).

So then, P must be in C3.
Now we have:
C1: N, W
C2: N
C3: P

And since G must be in a different center than P (Rule 3), we've got to put it in C1 AND C2. (Remember, we were looking for the second item that is shared between C2 and C1.)

Now we have:
C1: N, W, G
C2: N, G
C3: P

Finally, we've got to put T somewhere. Oh look, C3 needs another item.
Now we have:
C1: N, W, G
C2: N, G
C3: P, T

Now, you MAY be thinking "what if C3 has a third item?"
Ignore that thought for now. Let's look at the answer choices.

(A) This is C3, so this is our answer.
(B) Nope. C1 is the center with W, and it has N, W, G
(C) Nope. C3 has T, but no N.
(D) No. Again, C1 is the only center with W, and it has N, W, G.
(E) No again. C3 has T & P, not T, & G.

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Thanks,
Brendan Duffy
Founder, Arcadia Prep

Btw there are several ways which you can deduce this...mine was just the simplest in this context.

Why is the correct answer to 13 is A instead of B. It's the recycling question

Damien, this question has been explained thoroughly in one of the posts. Please look up the thread and you will find a setup and step by step walkthrough.

Disregard those last two posts on previous questions. You can delete them if you want. It's obvious c cannot be disproven without assuming that some centre must recycle each material. If glass did not need to be recycled we could have:
WNT
NT
P(T/N)

As c) is incorrect I must imagine that was an implicit rule though the phrasing still confuses me.

Hi sorry but it didn't say that EVERY item must be recycled..right? If Glass is left out then newsprint and tin is correct too, can I think of it in this way?

Igot it ..A is really the rite answer ...very simple