Bank deposits are credited on the date of the transaction

Question

Bank deposits are credited on the date of the transaction only when they are made before 3.pm. Alicia knows that the bank deposit was made before 3 p.m . So, Alicia knows that the bank deposit was credited on the date of the transaction.

Which one of the following exhibits both of the logical flaws exhibited by the argument above?

(A) Journalists are the only ones who will be permitted to ask questions at the press conference. Since Marjorie is a journalist, she will be permitted to ask questions.

(B) We know that Patrice works only on Thursday. Today is Thursday, so it follows that Patrice is working today.

(C) It is clear that George knows he will be promoted to shift supervisor, because George will be promoted to shift supervisor only if Helen resigns, and George knows Helen will resign.

(D) John believes that 4 is a prime number and that 4 is divisible by 2. Hence John believes that there is a prime number divisible by 2.

(E) Pat wants to become a social worker. It is well known that social workers are poorly paid. Pat apparently wants to be poorly paid.

alwynjoseph · Answer

I think the answer is statement B.

Target760 · Answer

phew! v difficult.

The statements seem to make following structure:
 
A)  X happens  (Bank deposits are credited on the date of the transaction)  only when Y happens  (when they are made before 3.pm). 
B)  because Y has happened  (Alicia knows that the bank deposit was made before 3 p.m . ),  therefore X would have happened   (So, Alicia knows that the bank deposit was credited on the date of the transaction.)

initially it feels C is correct; Statement C seems to have same structure: X will happen (George will be promoted to shift supervisor) only when Y will happen (only if Helen resigns). but if the second part of the statement had said that Helen 'has' resigned instead of 'will' resign, then the structure would have mactched.

but i would go for statement B: X happens (Patrice works) only when Y happens (only when its Thursday). X has happened (today is Thursday) therefore Y would have happened too (Patrice is working today)

my answer is B

mostwantedjatt · Answer

c

bipolarbear · Answer

OA is C. Two errors in reasoning, the second of which is "knowing"

Target760 · Answer

so i got i wrong. :-(

am sick of getting these difficult CR wrong. and its always between two narrow donw choices that i pick the wrong one. what to do? and what was second error in my reasoning other than knowing??

bipolarbear · Answer

This one was very difficult, so don't feel too bad 8-)

boeinz · Answer

this is tough. what is the source?

lalmanistl · Answer

i'm still not able to get which one is correct... can someone explain both B and C again???

-STL

sudeep · Answer

Nice question!

sprtng · Answer

nice question! B, C and even E looked like viable choices...but after reading it more thoroughly, B definitely is better!

kevincan · Answer

The key is to identify the two flaws in reasoning:

First, the author confuses a necessary condition with a sufficient condition. Secondly, he/she assumes that Alicia is aware of this condition

TommyWallach · Answer

Hey All,

This is a brutal question. It can be difficult to see what the "two logical flaws" mentioned in the question stem are referring to, and no one has yet explained them very clearly. Let's take apart the passage one more time, and see how the flaws are formed.

PASSAGE: Bank deposits are credited on the date of the transaction only when they are made before 3.pm. 
FLAW: This makes it sound as if any deposit made before 3 pm will be credited that same day. But that isn't true. All this says is that no deposit made AFTER 3 pm will be credited. All of the deposits made BEFORE 3pm DO NOT have to be credited.

PASSAGE: Alicia knows that the bank deposit was made before 3 p.m . So, Alicia knows that the bank deposit was credited on the date of the transaction.
FLAW: This would be true, if we could be sure that Alicia knew the first sentence of this passage. If she doesn't know the rule above (bank deposits credited on date only when made before 3pm), she wouldn't be able to make this logical inference.

Okay. Now we have a sense of both flaws. Let's look at the answer choices.

(A) Journalists are the only ones who will be permitted to ask questions at the press conference. Since Marjorie is a journalist, she will be permitted to ask questions.
PROBLEM: This has the FIRST flaw of our two. Journalists are the only ones who get to ask questions, but that doesn't mean every journalist gets to ask questions. Unfortunately, we're the SECOND flaw. To get flaw #2, we'd need Marjorie to assume she'd be permitted to ask questions.

(B) We know that Patrice works only on Thursday. Today is Thursday, so it follows that Patrice is working today.
PROBLEM: This has the FIRST flaw of our two again. Patrice works only on Thursdays, but that doesn't mean he works every Thursday. We're still missing the SECOND flaw, however.

(C) It is clear that George knows he will be promoted to shift supervisor, because George will be promoted to shift supervisor only if Helen resigns, and George knows Helen will resign.
ANSWER: This has BOTH flaws. The FIRST flaw is that "George will be promoted to shift supervisor only if Helen resigns" DOES NOT imply that George will definitely be promoted if she resigns. It just means he definitely won't be promoted if she isn't fired. The SECOND flaw is that we're assuming George KNOWS the rule we're told in the second part of the sentence (that we will be promoted only if Helen resigns)

(D) John believes that 4 is a prime number and that 4 is divisible by 2. Hence John believes that there is a prime number divisible by 2.
PROBLEM: As far as I can see (though I'm open to argument), there's NO flaw here. If John believes 4 is a prime number and divisible by 2, he believes there is a prime number divisible by 2.

(E) Pat wants to become a social worker. It is well known that social workers are poorly paid. Pat apparently wants to be poorly paid.
PROBLEM: This has the SECOND flaw from our original passage. We are not told that Pat KNOWS that social workers are poorly paid.

Hope that helps! Good question!

Bank deposits are credited on the date of the transaction

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