hi guys
my question is rather silly, but i still confused, and want somebody clarify my doubts
Does integer k have at least three different positive prime factors?
(1) k/15 is an integer
(2) k/10 is an integer
oa C
with some efforts i can solve this problem, finding LCM(10,15) and regarding that k=30m, where m is +ve integer
my question is
what if k=0, then 0/15, as well as 0/10=0 (we are not given any restrictions on k, for example k>0) , and the answer will be E
what i am missing here?
og problem
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- Gurpinder
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Do it this way:clock60 wrote:hi guys
my question is rather silly, but i still confused, and want somebody clarify my doubts
Does integer k have at least three different positive prime factors?
(1) k/15 is an integer
(2) k/10 is an integer
oa C
with some efforts i can solve this problem, finding LCM(10,15) and regarding that k=30m, where m is +ve integer
my question is
what if k=0, then 0/15, as well as 0/10=0 (we are not given any restrictions on k, for example k>0) , and the answer will be E
what i am missing here?
(1)
Since k/15 --> k has all the prime factors of 15. Therefore, the prime factors of K are 5,3....and more.... More because we do not know ALL the prime factors of K because we don't know what K is. We can only say that it has the prime factors of 15 because it is divisible by 15.
So 5,3.....more
Therefore this one is insufficient because we have 2 factors of K but we don't know whether there are more or not.
(2) k/10 --> so the prime factors of K are 5,2. Again these are only 2 and there might be more.
So this one is also insufficient.
Together:
We have 5,5,3,2, ...... more. Even though we might have more, we certainly have 3 distinct factors.
Therefore the answer is (C).
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
- Alfred A. Montapert, Philosopher.
- Gurpinder
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Well..... if k = 0 then the denominator can be anything, you will always get a zero. So there is an infinite number of factors. Every real number can be part of a factor pair with 0. So there are infinite factors and infinite factor pairs. So I dont think GMAT would test such thing.clock60 wrote:hi gurpinder
thank you for you reply, i will follow your way,
but what if K=0? many factors does 0 have?
Hmmm....you got me thinking.
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
- Alfred A. Montapert, Philosopher.
- Gurpinder
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well, come to think about it. the problem, the way it is worded now, is similar to the question you raised.
(1) k/15 is an integer
(2) k/10 is an integer
so the prime factors of K include 5,3,5,2................more. < this list could be infinitive since we dont know what K is. all we care about is 3 distinct prime factors. which we have. so i guess just dont worry about it. lol.
does that help a little?
(1) k/15 is an integer
(2) k/10 is an integer
so the prime factors of K include 5,3,5,2................more. < this list could be infinitive since we dont know what K is. all we care about is 3 distinct prime factors. which we have. so i guess just dont worry about it. lol.
does that help a little?
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
- Alfred A. Montapert, Philosopher.
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i am still not convinced, but don`t want to look stubborn,
let us imply that if k=0 the,the problem does not have meaning,
but for me the it will looks better if they add :where k is +ve integer
let us imply that if k=0 the,the problem does not have meaning,
but for me the it will looks better if they add :where k is +ve integer
- Gurpinder
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But to me k=0 doesn't rationalize. If it were 0, then it wouldnt even matter what statement 1,2 said because regardless of what information they give us, since technically zero is a multiple of every number, any number is a factor of zero. That wouldn't really be much of a question rather just knowing a rule!clock60 wrote:i am still not convinced, but don`t want to look stubborn,
let us imply that if k=0 the,the problem does not have meaning,
but for me the it will looks better if they add :where k is +ve integer
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
- Alfred A. Montapert, Philosopher.
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it seems that it is exactly the same what i want to hear, i missed this pointGurpinder wrote:But to me k=0 doesn't rationalize. If it were 0, then it wouldnt even matter what statement 1,2 said because regardless of what information they give us, since technically zero is a multiple of every number, any number is a factor of zero. That wouldn't really be much of a question rather just knowing a rule!clock60 wrote:i am still not convinced, but don`t want to look stubborn,
let us imply that if k=0 the,the problem does not have meaning,
but for me the it will looks better if they add :where k is +ve integer
thank you!!
- Gurpinder
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hahaha np!clock60 wrote:it seems that it is exactly the same what i want to hear, i missed this pointGurpinder wrote:But to me k=0 doesn't rationalize. If it were 0, then it wouldnt even matter what statement 1,2 said because regardless of what information they give us, since technically zero is a multiple of every number, any number is a factor of zero. That wouldn't really be much of a question rather just knowing a rule!clock60 wrote:i am still not convinced, but don`t want to look stubborn,
let us imply that if k=0 the,the problem does not have meaning,
but for me the it will looks better if they add :where k is +ve integer
thank you!!
"Do not confuse motion and progress. A rocking horse keeps moving but does not make any progress."
- Alfred A. Montapert, Philosopher.
- Alfred A. Montapert, Philosopher.