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# D01-12

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Intern
Joined: 20 May 2016
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01 Jul 2017, 08:01
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The question stem tells us that @ is either (0 or 5) as N is divisible by 5 .
I Think we can get a unique answer with statement A because 1 is not divisible by 5 whereas 5! is divisible by 5 .
I cannot understand why you have checked for @ {1,2,3,4} as we have already narrowed our search down to @{0,5}.
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Joined: 02 Sep 2009
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01 Jul 2017, 09:21
akshaypareek312 wrote:
Bunnel
The question stem tells us that @ is either (0 or 5) as N is divisible by 5 .
I Think we can get a unique answer with statement A because 1 is not divisible by 5 whereas 5! is divisible by 5 .
I cannot understand why you have checked for @ {1,2,3,4} as we have already narrowed our search down to @{0,5}.

You should read question and solution more carefully. The question does NOT say that @ equals to 0 or 5. The question asks whether @ equals to 0 or 5. From (1) if @ is 0, then the answer to the question is YES but if @ is 1, 2, 3, or 4, then the answer to the question is NO.
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19 Sep 2018, 01:38
@! is not divisible by 5. can be 0, 1, 2, 3, or 4 (note that 0!=1). Not sufficient.
Here N's Unit Digit is https://gmatclub.com:443/forum/memberlist.php?mode=viewprofile&un=, not @! so why you consider 0 here ... can be 1,2,3,4 only..
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19 Sep 2018, 02:47
ARVINDSHARMA wrote:
@! is not divisible by 5. can be 0, 1, 2, 3, or 4 (note that 0!=1). Not sufficient.
Here N's Unit Digit is https://gmatclub.com:443/forum/memberlist.php?mode=viewprofile&un=, not @! so why you consider 0 here ... can be 1,2,3,4 only..

0! = 1, which is NOT divisible by 5. So, $$@$$ be 0.
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09 Feb 2019, 23:48
I think this is a high-quality question and I agree with explanation.
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10 Feb 2019, 00:28
Bunuel wrote:
If $$N = 1234@$$ and $$@$$ represents the units digit of $$N$$, is $$N$$ a multiple of 5?

(1) $$@!$$ is not divisible by 5

(2) $$@$$ is divisible by 9

Lets do 3 things first

For N to be divisible by 5 @ has to be 0 or 5

Second 0! = 1

Third: zero is a multiple of every integer (except zero itself)

(1) $$@!$$ is not divisible by 5
@!, 0! = 1, when put back in the question, this will make N divisible by 5,, Yes
4! =24,when put back in the question, this will make N divisible by 5, No

(2) $$@$$ is divisible by 9[/quote]
m can be 0, this is / by 9, when put back in the question, this will make N divisible by 5, Yes
m can be 9, when put back in the question, this will make N divisible by 5,No

We have the common value from both the statements
0, making N divisible by 5

C
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04 Jul 2019, 22:32
I don't agree with the explanation. Aren’t we supposed to see if N is divisible by 5?
There are 5 options if we follow the 1st option and in all cases N isn’t divisible by 5 and thus that is sufficient

Posted from my mobile device
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04 Jul 2019, 22:47
Warraich54 wrote:
I don't agree with the explanation. Aren’t we supposed to see if N is divisible by 5?
There are 5 options if we follow the 1st option and in all cases N isn’t divisible by 5 and thus that is sufficient

Posted from my mobile device

You did not read the solution carefully enough.

From (1) $$@$$ can be 0, 1, 2, 3, or 4. If it's 0, then $$1234@$$ IS divisible by 5 but if $$@$$ is 1, 2, 3, or 4, then $$1234@$$ is NOT divisible by 5.
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27 Sep 2019, 23:50
I think this is a high-quality question and I agree with explanation.
Re D01-12   [#permalink] 27 Sep 2019, 23:50

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# D01-12

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