If x>1, what is the value of x
1) There are x unique factors of x.
2) The sum of x and any prime number larger than x is odd.
number properties
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- Ian Stewart
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I'm sure Statement 1 means to say "There are x distinct positive factors of x." I think it's easiest to see what this means by trying a number for x. If x were, say, 25, then this would say "25 has 25 distinct positive factors". That's clearly absurd; that would mean that 25 was divisible by every single number between 1 and 25. Indeed, x can never be divisible by *every* number between 1 and x if x is greater than 2, since if x > 2, x is never divisible by x-1. So if Statement 1 is true, x can only be 1 or 2, and since we know x > 1, x must be equal to 2.abhi332 wrote:If x>1, what is the value of x
1) There are x unique factors of x.
2) The sum of x and any prime number larger than x is odd.
Statement 2 is not sufficient; since x > 2, then any prime larger than x is odd. So Statement 2 only tells us that x is even.
The answer is A.
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IAN
Ans will be D
because
2 is only number in which if u add any other prime no , summation will be ODD
Thanks.....
Ans will be D
because
2 is only number in which if u add any other prime no , summation will be ODD
Thanks.....
- papgust
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girish3131 wrote:IAN
Ans will be D
because
2 is only number in which if u add any other prime no , summation will be ODD
Thanks.....
Nope. Any even integer added with a prime number greater than 2 will be ODD. I guess you stole information from statement I and confused yourself.
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if u take any no ( except 2 ) and then add any prime number ( obviously greater than the number wch u have taken then their sum will be EVEN )
N when u take x= 2 and add any prime no then sum is ODD
this is sufficient to say X IS ONLY 2
hence ans is D
if u still disagree then give ex wch contradict my expalanation....
ta
N when u take x= 2 and add any prime no then sum is ODD
this is sufficient to say X IS ONLY 2
hence ans is D
if u still disagree then give ex wch contradict my expalanation....
ta
- firdaus117
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x=4 prime number greater than 4=5 4+5=9 :An odd numbergirish3131 wrote:if u take any no ( except 2 ) and then add any prime number ( obviously greater than the number wch u have taken then their sum will be EVEN )
N when u take x= 2 and add any prime no then sum is ODD
this is sufficient to say X IS ONLY 2
hence ans is D
if u still disagree then give ex wch contradict my expalanation....
ta
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