18. If x and y are nonzero integers, is(x/y) an integer?
(1) x is the product of 2 and some other integer.
(2) There is only one pair of positive integers whose product equals y.
I am little curious ! to know the approach
OA E
took a little too long to solve this !!
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Vishu,
Stmt I)
tell us x is even No info about y INSUFF
Stmt II
tells us y is prime No info about x INSUFF
Taking 2 together still INSUFF
X/Y IS AN INTEGER IF PRIME y=2(still dont know if y is in fact 2 could be any other primes wiht may/may not be cases)
We can stop rught here and mark E)
Eg: 2*4 = 8 / 3 not an integer
2*6 / 3 = integer
INSUFF
Hope I have not missed something here!
E)
Stmt I)
tell us x is even No info about y INSUFF
Stmt II
tells us y is prime No info about x INSUFF
Taking 2 together still INSUFF
X/Y IS AN INTEGER IF PRIME y=2(still dont know if y is in fact 2 could be any other primes wiht may/may not be cases)
We can stop rught here and mark E)
Eg: 2*4 = 8 / 3 not an integer
2*6 / 3 = integer
INSUFF
Hope I have not missed something here!
E)
- logitech
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Are you only a little bit curious ? Then I should only tell a little bit of my approachvishubn wrote:18. If x and y are nonzero integers, is(x/y) an integer?
(1) x is the product of 2 and some other integer.
(2) There is only one pair of positive integers whose product equals y.
I am little curious ! to know the approach
OA E
1 and 2 both gives us separate info about X and Y so it is either C or E
1) X = 2K , where K is some other integer. So X is not equal to 4
2) y = Prime ^ 2
1+2) it is not 4/4 - which was close
but it is 2X/Prime Prime = ? It can or not be an integer, Hence E
X=49
Y=49
SUF
X=3
Y=25
NOPE
TATAM!!
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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yaaa ! was concerned ! that i took around 3 mins ! looked eassy when solving but realized the time !!
Thanks u guys
Vishu
ps. i know the well know quote in the forum about the 2:00 and 2:30 mins
Thanks u guys
Vishu
ps. i know the well know quote in the forum about the 2:00 and 2:30 mins
KILL !! DIE !! or BEAT my FEAR !!! de@D END!!
- logitech
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You are right cramya. I think the wording cannot be translated into what I came up with.cramya wrote:2) y = Prime ^ 2
I am not so sure on the y=prime^2 part
1 pair of positive integers in the sense (1,2) or (2,1) ; (1,3) or (3,1)
Regards,
Cramya
How about y=prime ? ( Nx1)
LGTCH
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- Stuart@KaplanGMAT
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Just a quick note:
"There is only one pair of positive integers whose product equals y."
Y could be prime, but y could also equal 1, since only one pair of positive integers (1*1) equals 1.
Without the word "distinct" in the statement, we can't assume that the integers must be different.
(E) is, of course, still the correct answer.
"There is only one pair of positive integers whose product equals y."
Y could be prime, but y could also equal 1, since only one pair of positive integers (1*1) equals 1.
Without the word "distinct" in the statement, we can't assume that the integers must be different.
(E) is, of course, still the correct answer.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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