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by ajith » Thu Feb 11, 2010 12:29 pm
Amiman wrote:If x is a prime no. then what is the value of x?
1. x<15
2.(x-2) is a multiple of 5
1. Is insufficient (2,3,5,7,11 and 13 are less than 15)
2.) x-2 is a multiple of 5 is not sufficient (7, 17,37 all satisfy this


1 & 2 combined is sufficient
Only 7 falls into the criterion

Hence C
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by Osirus@VeritasPrep » Thu Feb 11, 2010 12:31 pm
ajith wrote:
Amiman wrote:If x is a prime no. then what is the value of x?
1. x<15
2.(x-2) is a multiple of 5
1. Is insufficient (2,3,5,7,11 and 13 are less than 15)
2.) x-2 is a multiple of 5 is not sufficient (7, 17,37 all satisfy this


1 & 2 combined is sufficient
Only 7 falls into the criterion

Hence C
Is 0 not a multiple of 5? If so wouldn't the answer be E?
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by ajith » Thu Feb 11, 2010 12:40 pm
osirus0830 wrote:
Is 0 not a multiple of 5? If so wouldn't the answer be E?
That's a thought - In that way zero is a multiple of every number.

https://en.wikipedia.org/wiki/Multiple_(mathematics)
https://www.beatthegmat.com/is-zero-to-b ... t4268.html

Search helps!

E yes, indeed
Last edited by ajith on Thu Feb 11, 2010 12:42 pm, edited 1 time in total.
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by Osirus@VeritasPrep » Thu Feb 11, 2010 12:41 pm
ajith wrote:[quote="osirus0830"

Is 0 not a multiple of 5? If so wouldn't the answer be E?
That's a thought - In that way zero is a multiple of every number.

https://en.wikipedia.org/wiki/Multiple_(mathematics)
https://www.beatthegmat.com/is-zero-to-b ... t4268.html

Search helps!

E yes, indeed[/quote]

You're slipping, I consider you the quant guru...lol
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by ajith » Thu Feb 11, 2010 12:45 pm
osirus0830 wrote:
You're slipping, I consider you the quant guru...lol
I am not a Guru and I have equal right to make mistakes as anybody else. Having said that of late, I agree I am making a lot of errors. Only thing I can assure you is none of these are intentional.
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by Osirus@VeritasPrep » Thu Feb 11, 2010 12:47 pm
ajith wrote:
osirus0830 wrote:
You're slipping, I consider you the quant guru...lol
I am not a Guru and I have equal right to make mistakes as anybody else. Having said that of late, I agree I am making a lot of errors. Only thing I can assure you is none of these are intentional.
I was kidding, I think you are one of the top guys in math on the board, it was a mistake that we all have made before, no worries.
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by gmatmachoman » Thu Feb 11, 2010 12:48 pm
osirus0830 wrote:
ajith wrote:
Amiman wrote:If x is a prime no. then what is the value of x?
1. x<15
2.(x-2) is a multiple of 5
1. Is insufficient (2,3,5,7,11 and 13 are less than 15)
2.) x-2 is a multiple of 5 is not sufficient (7, 17,37 all satisfy this


1 & 2 combined is sufficient
Only 7 falls into the criterion

Hence C
Is 0 not a multiple of 5? If so wouldn't the answer be E?
C is the answer.

Soln:
No. of prime numbers less than 15 : 2,,5,7,11 & 13.

Using 1 alone, we cannot decisivley say the value of X.

SO A & D are eliminated.


SO let us come to 2:

(x-2) is a multiple of 5:

We have couple of cases brewing up:

When X =2 ,--> X- 2= 0 which is a NOT muliple of 5( Osirus, ur query is being answered)

& as per ajith, when X=7 , rigthly fits the condition.

SO using both 1 & 2 we can precisely state the value of X=7
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by Osirus@VeritasPrep » Thu Feb 11, 2010 12:51 pm
What's the source? Everything I'm reading says that 0 is a multiple of every number.
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by ajith » Thu Feb 11, 2010 12:55 pm
gmatmachoman wrote: When X =2 ,--> X- 2= 0 which is a NOT muliple of 5( Osirus, ur query is being answered)
Well, That is what I thought initially too, but zero is a multiple of every number. Please find the discussion on the same question and the wiki link for the definition of multiple. (wiki link even has a 0*7 =0 example)

So, Now I am convinced that zero is a multiple of 5.
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by gmatmachoman » Thu Feb 11, 2010 1:03 pm
ajith wrote:
gmatmachoman wrote: When X =2 ,--> X- 2= 0 which is a NOT muliple of 5( Osirus, ur query is being answered)
Well, That is what I thought initially too, but zero is a multiple of every number. Please find the discussion on the same question and the wiki link for the definition of multiple. (wiki link even has a 0*7 =0 example)

So, Now I am convinced that zero is a multiple of 5.
Agreed Ajith,...

That was silly of me!!Sorry!Error in Maths..OMG..Unacceptable..actually tried to delete that post, but it said i cant as Osiru s has replied..Shamefu!
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by Amiman » Thu Feb 11, 2010 2:39 pm
Thanks Ajith. I too made the same mistake initially of ignoring 0. So, I thought to check with you guys.
The source is Kaplan.
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