If x is an integer greater than 1, is x equal to 2^k for some
positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
I still don't understand this. How is it B? All statement 2 says is X is 2 to the something. Whether X =2^k depends on what K is. It could and it couldnt.
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Number Property
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gmatusa2010
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When every factor of x is even, it basically means that x should have factors which are powers of 2.gmatusa2010 wrote:If x is an integer greater than 1, is x equal to 2^k for some
positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
I still don't understand this. How is it B? All statement 2 says is X is 2 to the something. Whether X =2^k depends on what K is. It could and it couldnt.
Example, if x has a factor of 6, then it means it has a factor of 3 as well. Hence, if every factor of x is even, then x should be a power of 2 or in other words, x = 2^k.
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goyalsau
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gmatusa2010 wrote:If x is an integer greater than 1, is x equal to 2^k for some
positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
I still don't understand this. How is it B? All statement 2 says is X is 2 to the something. Whether X =2^k depends on what K is. It could and it couldnt.
(2) Every factor of x is even. { Is this statement Wrong}
Every positive Integer will have 1 as a factor.
Eg. 2^4 = 16
Factors are 1 , 2 , 4 , 8 , 16
So according to me every positive integer will always have a odd factor . i.e. 1
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gmatusa2010
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let's say X = 4 and k is 6 then 4 is not equal to 64. u can run many examples. unless it says can x= 2^k then i think you might be able to put B
ragz wrote:When every factor of x is even, it basically means that x should have factors which are powers of 2.gmatusa2010 wrote:If x is an integer greater than 1, is x equal to 2^k for some
positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
I still don't understand this. How is it B? All statement 2 says is X is 2 to the something. Whether X =2^k depends on what K is. It could and it couldnt.
Example, if x has a factor of 6, then it means it has a factor of 3 as well. Hence, if every factor of x is even, then x should be a power of 2 or in other words, x = 2^k.
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gmatusa2010
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the statement is correct and u are right. but i think its implying that X is even. Also, the explanation said so. let's just say they explicitly state that every factor greater than 1 is even. would the problem still make sense to you?
goyalsau wrote:gmatusa2010 wrote:If x is an integer greater than 1, is x equal to 2^k for some
positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
I still don't understand this. How is it B? All statement 2 says is X is 2 to the something. Whether X =2^k depends on what K is. It could and it couldnt.
(2) Every factor of x is even. { Is this statement Wrong}
Every positive Integer will have 1 as a factor.
Eg. 2^4 = 16
Factors are 1 , 2 , 4 , 8 , 16
So according to me every positive integer will always have a odd factor . i.e. 1
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Anurag@Gurome
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Statement 1: x has only one prime factor.gmatusa2010 wrote:If x is an integer greater than 1, is x equal to 2^k for some
positive integer k?
(1) x has only one prime factor.
(2) Every factor of x is even.
x can be any prime integer.
Not Sufficient.
Statement 2: Every factor of x is even.
It is possible when x has only 2 as its prime factor.
Thus x will be always of the form 2^k, for some positive integer k.
Sufficient.
The correct answer is B
The question asks "is x equal to 2^k for some positive integer k?"gmatusa2010 wrote:let's say X = 4 and k is 6 then 4 is not equal to 64. u can run many examples. unless it says can x= 2^k then i think you might be able to put B
It doesn't ask whether x is of the form 2^k for all positive integer k. Thus for x = 4, x is of the form 2^k for k = 2.
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lunarpower
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um ... what's the source of the problem?
because this statement
the number 1, which is odd, is a factor of EVERY positive integer; therefore, it's impossible for "every factor of x" to be even.
sketchy sketchy...
because this statement
is impossible.Every factor of x is even
the number 1, which is odd, is a factor of EVERY positive integer; therefore, it's impossible for "every factor of x" to be even.
sketchy sketchy...
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Voit esittää kysymyksiä Ron:lle myös suomeksi
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goyalsau
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thanks Ron..lunarpower wrote:um ... what's the source of the problem?
because this statementis impossible.Every factor of x is even
the number 1, which is odd, is a factor of EVERY positive integer; therefore, it's impossible for "every factor of x" to be even.
sketchy sketchy...
Saurabh Goyal
[email protected]
-------------------------
EveryBody Wants to Win But Nobody wants to prepare for Win.
[email protected]
-------------------------
EveryBody Wants to Win But Nobody wants to prepare for Win.
