PrepTest 78, Game 2, Question 8
Transcript
This is the third question from PT78, game number 2. And it asks if both R and Y are assigned to the project, which of the following could be true? So here we have a local question. And the new information for this question is that R and Y are assigned to the project.
So let's go ahead and recopy this diagram on our scratch paper just for this problem. This would be a local diagram. And I'm gonna go ahead and put Y in and R in. And if the R is in, that means R has to go to 1922, because you need room for the O immediately before it.
So if R is in, it's in 22, that means O is in 1921, because I also have to put Y in based on the question. That means Y is gonna have to go to 1924. That means at this point that the two students who are left out, one of them is gonna be our M and the other one is going to be either T or L, whichever one is not in 1923 is gonna go out.
Be careful not to think that the T has to go in right now, because based on rule number 3, if T is in, that means R is in. But just because R is in, that doesn't force the T to be in, so that's why I'm not gonna make 1923 a T, because it could be an L instead. Let's see what could be true. A says L is assigned to 1923.
Well, yeah, that could be true. This is our answer. If you got this far and you didn't pick answer choice A, that's probably because you thought R automatically brings T, but that's reading the rule backwards. You can see that M has to go out, so B can't be true. O has to go to 1, so it's not gonna go to 2.
D says T is assigned to 1924, but no, Y is in 4. And E says Y is assigned at 1922, but actually Y is in 1924.
Read full transcriptSo let's go ahead and recopy this diagram on our scratch paper just for this problem. This would be a local diagram. And I'm gonna go ahead and put Y in and R in. And if the R is in, that means R has to go to 1922, because you need room for the O immediately before it.
So if R is in, it's in 22, that means O is in 1921, because I also have to put Y in based on the question. That means Y is gonna have to go to 1924. That means at this point that the two students who are left out, one of them is gonna be our M and the other one is going to be either T or L, whichever one is not in 1923 is gonna go out.
Be careful not to think that the T has to go in right now, because based on rule number 3, if T is in, that means R is in. But just because R is in, that doesn't force the T to be in, so that's why I'm not gonna make 1923 a T, because it could be an L instead. Let's see what could be true. A says L is assigned to 1923.
Well, yeah, that could be true. This is our answer. If you got this far and you didn't pick answer choice A, that's probably because you thought R automatically brings T, but that's reading the rule backwards. You can see that M has to go out, so B can't be true. O has to go to 1, so it's not gonna go to 2.
D says T is assigned to 1924, but no, Y is in 4. And E says Y is assigned at 1922, but actually Y is in 1924.
