Statement 1 :beat_gmat_09 wrote:If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
(1) If x^3 + x is divisible by 4, then x^3 + x is even, x could be either even or odd. Insufficientbeat_gmat_09 wrote:If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
sooooper!!!sanju09 wrote:(1) If x^3 + x is divisible by 4, then x^3 + x is even, x could be either even or odd. Insufficientbeat_gmat_09 wrote:If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
(2) If 5 x + 4 is divisible by 6, then 5 x is even; and x may or may not be even here (what if x is 8/5?). Insufficient
Taken together, (1) confirms x is an integer and (2) confirms that 5 x is even, therefore x is even. [spoiler]Sufficient
C[/spoiler]
thanks mate!
harshavardhanc wrote:sooooper!!!sanju09 wrote:(1) If x^3 + x is divisible by 4, then x^3 + x is even, x could be either even or odd. Insufficientbeat_gmat_09 wrote:If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
(2) If 5 x + 4 is divisible by 6, then 5 x is even; and x may or may not be even here (what if x is 8/5?). Insufficient
Taken together, (1) confirms x is an integer and (2) confirms that 5 x is even, therefore x is even. [spoiler]Sufficient
C[/spoiler]
didn't pay attention to this fact.
outreach wrote:but (8/5) is divisible by 2. The Q asks if x is divisible by 2
i think the ans should be B
harshavardhanc wrote:sanju09 wrote:(1) If x^3 + x is divisible by 4, then x^3 + x is even, x could be either even or odd. Insufficientbeat_gmat_09 wrote:If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
(2) If 5 x + 4 is divisible by 6, then 5 x is even; and x may or may not be even here (what if x is 8/5?). Insufficient
Taken together, (1) confirms x is an integer and (2) confirms that 5 x is even, therefore x is even. [spoiler]Sufficient
C[/spoiler]
sooooper!!!
didn't pay attention to this fact.
IMO Ans is Dharshavardhanc wrote:outreach wrote:but (8/5) is divisible by 2. The Q asks if x is divisible by 2
i think the ans should be B
harshavardhanc wrote:sanju09 wrote:(1) If x^3 + x is divisible by 4, then x^3 + x is even, x could be either even or odd. Insufficientbeat_gmat_09 wrote:If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
(2) If 5 x + 4 is divisible by 6, then 5 x is even; and x may or may not be even here (what if x is 8/5?). Insufficient
Taken together, (1) confirms x is an integer and (2) confirms that 5 x is even, therefore x is even. [spoiler]Sufficient
C[/spoiler]
sooooper!!!
didn't pay attention to this fact.
So what about 5/3? is it divisible by 2? No? How about 10/6? Now is it divisible?
divisibility rules don't apply to fractions. Hence, Sanju's approach is correct. The answer should be C.
It's very hard to disagree with you here, really!!papumba2011 wrote:In case of stmt 1.
It is given x(x^2+1) is multiple of 4.
In all the discussion above, i think when considering whether x is even or odd we forgot to maintain x(x^2 + 1) to be divisible by 4.
If x is even and not a multiple of 4 then x(x^2 + 1) cannot be a multiple of 4.
for example x = 2 , then x(x^2 + 1) becomes 2 * 5 which is not didvidible by 4. Similar is the case for 6, 10 , etc.
So x must be a multiple of 4 itself.
If x is odd, x^2 +1 need to be multiple of 4 which again is not possible. Consider values of x to be 3, 5, 7, 9 , etc.
Hence from stmt 1 , x must always be multiple of 4 for x(x^2 + 1) to be multiple of 4.
Hence stmt 1 is sufficient.
In case of stmt well as pointed out in earlier post it is insufficient.
Hence answer is A.
Please let me know whether I am wrong.
yes, it is very correct! thanks you ppl!sanju09 wrote:
It's very hard to disagree with you here, really!!
[spoiler]heart changed to A[/spoiler]
How stupid am I?harshavardhanc wrote: Try to find out whether for any X, is X^2 + 1 divisible by 4? X in that case would have to be odd. try for 5, 7, 9, 13 ....
you'll find that for X=13, (X^2 + 1) becomes a multiple.
:roll: can't I distinguish between + and - ???? The one for the road had been the heaviest one perhaps, hence it resulted in few accidents (see in bold)kstv wrote:Seems party here is over , so one for the road.
If x is positive is x divisible by 2 ?
(1) x^3+x is divisible by 4
(2) 5x+4 is divisible by 6
(2) 5x+ 4 is divisible by 6 so 5x-2 is divisible by 6 (5x+4 - 6) = 5x - 2
5x - 2 if it is divisible by 6 it has to be divisible by 2 & 3
if 5x-2 is divisible by 2 then , 5x (5x-2+2) is divisible by 2
so 5x +4 is divisible by 2 Sufficient.
(1) x(x²+1) is divisible by 4 so either x is divisible by 4 or (x²+1) is divisible by 4
It is not possible that x is divisible just by 2 then x is even and (x²+1) has to be odd
what if x is odd of the form 2a+1 then x²+1 = 4a²+4a+1 + 1 this is divisible by 2 not 4
so x is a multiple of 4 Sufficient
IMO D
It says nothing concrete about x, I suppose.kstv wrote:@ sanju09 Hi ! Hic !
if 5x + 4 is divisible by 2,
do you agree with this part
If so what does it say about x
