Integer or not

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Integer or not

by mchaubey » Wed Apr 14, 2010 3:14 pm
If the integers v and w are both positive, is v/w an integer?

(1) For every factor n of w, n is also a factor of v.

(2) For every prime factor p of w, p is also a prime factor of v.


Here I came to conclusion that both the statements are suff. D

My friend said neither are because we dont know weather v>w. E

The solution stated only statement (1) is suff. A

Can some one help me out with this one.
Source: — Data Sufficiency |

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by liferocks » Wed Apr 14, 2010 5:44 pm
from condition 1 For every factor n of w, n is also a factor of v
now every number is one of its own factor.hence condition 1 clearly states that V is divisible by W-->sufficient

from condition 2 For every prime factor p of w, p is also a prime factor of v.
now there cab be possibility that V and W share same prime factors but foes not share the composite factors
ex V=6 and W=12..both are divisible by either 2 or 3 but 6 is not divisible by 12 because 4 is a factor of 12 but not of 6 hence this is insufficient.
[spoiler]Ans is A [/spoiler]
please put the answer in spoiler.It helps us solving the question independently.

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by sanju09 » Thu Apr 15, 2010 12:42 am
mchaubey wrote:If the integers v and w are both positive, is v/w an integer?

(1) For every factor n of w, n is also a factor of v.

(2) For every prime factor p of w, p is also a prime factor of v.


Here I came to conclusion that both the statements are suff. D

My friend said neither are because we dont know weather v>w. E

The solution stated only statement (1) is suff. A

Can some one help me out with this one.
Statement (1) talks about all factors identical, hence the two positive integers are the same positive integer, and their ratio is 1, an integer. Sufficient

Statement (2) talks about all prime factors identical, hence the two positive integers may or may not be the same positive integer or the numerator integer could be less or more than the denominator integer to spoil the party. Insufficient
[spoiler]
A[/spoiler]
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by liferocks » Thu Apr 15, 2010 1:43 am
sanju09 wrote:Statement (1) talks about all factors identical, hence the two positive integers are the same positive integer, and their ratio is 1, an integer. Sufficient
the two positive integers not necessarily has to be same but one will be multiple of another i.e v is a multiple of W or
v=nw where n is any integer ,if it is 1 then they are identical else not
Ex v=12 and w=6

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by sanju09 » Thu Apr 15, 2010 3:52 am
liferocks wrote:
sanju09 wrote:Statement (1) talks about all factors identical, hence the two positive integers are the same positive integer, and their ratio is 1, an integer. Sufficient
the two positive integers not necessarily has to be same but one will be multiple of another i.e v is a multiple of W or
v=nw where n is any integer ,if it is 1 then they are identical else not
Ex v=12 and w=6
Please read this statement one more time
(1) For every factor n of w, n is also a factor of v.


Doesn't it mean that all factors of w are factors of v as well? Oh yes! This way, w is a certain multiple or factor of v. Now, v/w an integer or not, remains mystery.

[spoiler]who was screaming Eeeeeeeeeeeee...?[/spoiler]
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by liferocks » Thu Apr 15, 2010 9:25 am
sanju09 wrote:
liferocks wrote:
sanju09 wrote:Statement (1) talks about all factors identical, hence the two positive integers are the same positive integer, and their ratio is 1, an integer. Sufficient
the two positive integers not necessarily has to be same but one will be multiple of another i.e v is a multiple of W or
v=nw where n is any integer ,if it is 1 then they are identical else not
Ex v=12 and w=6
Please read this statement one more time
(1) For every factor n of w, n is also a factor of v.


Doesn't it mean that all factors of w are factors of v as well? Oh yes! This way, w is a certain multiple or factor of v. Now, v/w an integer or not, remains mystery.

[spoiler]who was screaming Eeeeeeeeeeeee...?[/spoiler]
Please read the statement carefully..it says 'every factor n of w, n is also a factor of v' so v is a multiple of w or w is a factor of v,not 'w is a certain multiple'..so v/w definitely integer.

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by gmatmachoman » Fri Apr 16, 2010 12:29 am
liferocks wrote:
sanju09 wrote:Statement (1) talks about all factors identical, hence the two positive integers are the same positive integer, and their ratio is 1, an integer. Sufficient
the two positive integers not necessarily has to be same but one will be multiple of another i.e v is a multiple of W or
v=nw where n is any integer ,if it is 1 then they are identical else not
Ex v=12 and w=6
Bro ,

coming to u r case ,

what if V =6 & w = 12??

V/W wont be a integer.. So as per Sanju bhai Gyan...both v & w are the same and the ratio of V:W = 1

Kya Sanju Bhai Sahi na?? Sanju u owe me a thx now!!

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by liferocks » Fri Apr 16, 2010 12:51 am
gmatmachoman wrote:what if V =6 & w = 12??
if this is the case then the condition 'For every factor n of w, n is also a factor of v.' will not hold true .because
factors of V 1,2,3,6
factors of W 1,2,3,4,,12

so for n=4 or 12 the condition does not hold good

so it has to be the other way round i.e v=12 and w=6

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by gmatmachoman » Fri Apr 16, 2010 1:25 am
liferocks wrote:
gmatmachoman wrote:what if V =6 & w = 12??
if this is the case then the condition 'For every factor n of w, n is also a factor of v.' will not hold true .because
factors of V 1,2,3,6
factors of W 1,2,3,4,,12

so for n=4 or 12 the condition does not hold good

so it has to be the other way round i.e v=12 and w=6
Now Sanju, u have to convince him!!

@Lrocks!!

So only we said V & W are one and the same!!!

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by harshavardhanc » Fri Apr 16, 2010 1:27 am
liferocks wrote:
gmatmachoman wrote:what if V =6 & w = 12??
if this is the case then the condition 'For every factor n of w, n is also a factor of v.' will not hold true .because
factors of V 1,2,3,6
factors of W 1,2,3,4,,12

so for n=4 or 12 the condition does not hold good

so it has to be the other way round i.e v=12 and w=6

Precisely. I'm with liferocks here. Statement 1 just says that every factor of W is a factor of V. It doesn't mean that the number of factors is same.

Look at this way :

set of factors of W is a subset of set of factors of V. Having equal number of elments in both is just one of the possibility.

Either way, V/W will be an integer.

Statement2 :

It just tells us that the prime factors are same : i.e if W has 2,3, and 5 as the prime factors, V also has 2,3, and 5.

But we don't know the exact power of each prime factor. Hence, it is insufficient.

Therefore, the answer is A.
Regards,
Harsha

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by gmatmachoman » Fri Apr 16, 2010 1:46 am
mchaubey wrote:If the integers v and w are both positive, is v/w an integer?

(1) For every factor n of w, n is also a factor of v.



.
Let us split the stem given :

Let W =12
factors : 1, 2,3, 4,6,12

Let V =??( could be 24/36..any mulitple of W)

Factors : 1, 2, 3, 4,6, 12 , X, Y ........N

Now it means V >=W .

Harsha, u are also correct. Its not that V has to be equal to W, It can also be greater than W provided V is a multiple of W!!

Agreed???

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by liferocks » Fri Apr 16, 2010 1:57 am
gmatmachoman wrote:
mchaubey wrote:If the integers v and w are both positive, is v/w an integer?

(1) For every factor n of w, n is also a factor of v.



.
Let us split the stem given :

Let W =12
factors : 1, 2,3, 4,6,12

Let V =??( could be 24/36..any mulitple of W)

Factors : 1, 2, 3, 4,6, 12 , X, Y ........N

Now it means V >=W .

Harsha, u are also correct. Its not that V has to be equal to W, It can also be greater than W provided V is a multiple of W!!

Agreed???
finally we all are in the same page bro..this it what i am saying ,V is a multiple of W ,,they can be equal if multiplicity factor is 1 but its not necessary that they are equal :)

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by gmatmachoman » Fri Apr 16, 2010 2:02 am
liferocks wrote:
gmatmachoman wrote:
mchaubey wrote:If the integers v and w are both positive, is v/w an integer?

(1) For every factor n of w, n is also a factor of v.



.
Let us split the stem given :

Let W =12
factors : 1, 2,3, 4,6,12

Let V =??( could be 24/36..any mulitple of W)

Factors : 1, 2, 3, 4,6, 12 , X, Y ........N

Now it means V >=W .

Harsha, u are also correct. Its not that V has to be equal to W, It can also be greater than W provided V is a multiple of W!!

Agreed???
finally we all are in the same page bro..this it what i am saying ,V is a multiple of W ,,they can be equal if multiplicity factor is 1 but its not necessary that they are equal :)
Agreed Mr Rocks!!

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by sanju09 » Fri Apr 16, 2010 4:03 am
If every factor of w is a factor of v, then v/w is an integer. But, is this what the statement (1) exactly saying?

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by gmatmachoman » Sun Apr 18, 2010 9:01 pm
sanju09 wrote:If every factor of w is a factor of v, then v/w is an integer. But, is this what the statement (1) exactly saying?

You always deserve my thanks, Govind Moshai, specially when you are on the wrongside of road all in order to follow me
hehehehe

Sanju.. thx fo tat Thx buttoning!!LOL! Actually we were bit hasty in deciphering the statement 1!!