5x is divisible by 2 , 5 is odd so x has to be divisible by 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
Twist in my sobriety.
Divisibility
- sanju09
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Dear Drunkard, if 5 x is even, we are never sure about x, it may be an even integer, but at the same time it may not! Again saying...what if x is 2/5 or 8/5 etc?kstv wrote:5x is divisible by 2 , 5 is odd so x has to be divisible by 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
Twist in my sobriety.
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
- harshavardhanc
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sanju09 wrote:Dear Drunkard, if 5 x is even, we are never sure about x, it may be an even integer, but at the same time it may not! Again saying...what if x is 2/5 or 8/5 etc?kstv wrote:5x is divisible by 2 , 5 is odd so x has to be divisible by 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
Twist in my sobriety.
ahhhh!!!!! I smell spirit........
Kstv,
That's where it all started...........we are just given that 5X+2 is divisible by 2. However, it is not said that X is an integer and hence, you cannot assume it to be one.
Cheers!!! hik! :mrgreen:
Regards,
Harsha
Harsha
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gmatmachoman
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Guys, seems I have missed a lot of action...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
Anyways now I am in...
St 1: as discussed X should be a multiple of 4. So X is divisible by 2.
Sufficient
St 2:5x+4 is divisible by 6
Try X=4,10,14,22,34,40....( seems it floows a pattern)
X is divisible by 2.
SO D..
Agreed???
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nopesgmatmachoman wrote:Guys, seems I have missed a lot of action...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
Anyways now I am in...
St 1: as discussed X should be a multiple of 4. So X is divisible by 2.
Sufficient
St 2:5x+4 is divisible by 6
Try X=4,10,14,22,34,40....( seems it floows a pattern)
X is divisible by 2.
SO D..
Agreed???
seems like you have not only missed actions here, but few reactions as well
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
- thephoenix
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i do agree ITS D but the pattern for s2 is 4,10,16,22,28,34,40,46,52,58,64...............gmatmachoman wrote:Guys, seems I have missed a lot of action...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
Anyways now I am in...
St 1: as discussed X should be a multiple of 4. So X is divisible by 2.
Sufficient
St 2:5x+4 is divisible by 6
Try X=4,10,14,22,34,40....( seems it floows a pattern)
X is divisible by 2.
SO D..
Agreed???
and sanju i dnt understand how come x=2/5 makes 5x+4 div by 6
and for x=8/5 5x+4 is div by 6 and so is x div by 2
- sanju09
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At x = 2/5 or 8/5, 5 x + 4 = 6 or 12 respectively, each divisible by 6; but since these values of x are not integral, we cannot call them even/odd. So, (2) is insufficient.and sanju i dnt understand how come x=2/5 makes 5x+4 div by 6
and for x=8/5 5x+4 is div by 6 and so is x div by 2
The mind is everything. What you think you become. -Lord Buddha
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
Sanjeev K Saxena
Quantitative Instructor
The Princeton Review - Manya Abroad
Lucknow-226001
www.manyagroup.com
- harshavardhanc
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ha ha! I think this is never going to end....thephoenix wrote: i do agree ITS D but the pattern for s2 is 4,10,16,22,28,34,40,46,52,58,64...............
and sanju i dnt understand how come x=2/5 makes 5x+4 div by 6
and for x=8/5 5x+4 is div by 6 and so is x div by 2
thephoenix,
5 * (2/5) + 4 = 6 which is divisible by 6.
5 * (8/5) + 4 = 12 which is divisible by 6.
if you say 8/5 is divisible by 2, tell me is 1 / (5/8) divisible by 2 ? No. but the fraction is same !
The fact is you can only classify integers as even / odd , or apply divisibility rules to integers. Not to any fraction.
That's what Sanju said :
statement 2 never says that X is an integer and hence, you cannot assume X to be an integer.
Regards,
Harsha
Harsha












