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Given that x& = x^2 + 3, what is the value of integer k if there is a
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Updated on: 24 Jan 2018, 04:42
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Given that x& = x^2 + 3, what is the value of integer k if there is a remainder of 3 when k& is divided by 4? (1) 16 < k& < 37 (2) k is a factor of 24. (A). In statement 1, there are two possible values for k&: 19 and 28. Only 19 has a 11 The Princeton Review Management, LLC 2002 remainder of 3 when divided by 4, however, so statement 1 is sufficient. All even values of k will have a remainder of 3 when divided by 4 (can you explain why this is so?), so statement 2 does not give you enough information. Can someone please explain this to me? Why are 19 and 28 the only possibility in statement 1?
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Originally posted by nehalkapadi123 on 24 Jan 2018, 03:44.
Last edited by Bunuel on 24 Jan 2018, 04:42, edited 3 times in total.
Renamed the topic, edited the question and the OA.



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 04:25
nehalkapadi123 wrote: Given that x& = x^2 + 3, what is the value of integer k if there is a remainder of 3 when k& is divided by 4?
(1) 16 < k& < 37 (2) k is a factor of 24.
Can someone please explain this to me? Why are 19 and 28 the only possibility in statement 1? hi K&=K^2+3.. so k^2+3 when divided by 4 leaves a remainder of 3.. so K^2 must be divisible by 4... so k could be any even number 1)16<K&<37 \(16<K^2+3<37\).... \(K^2+3>16.....K^2>13...\) so K >3 and K is an integer \(K^2+3<37.....K^2<36..\) .so K<6 possible values of K are 4 and 5 but 5^2 is not div by 4, so our answer 4.. suff 2) K is a factor of 24 nothing much insuff A
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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 04:31
chetan2u wrote: nehalkapadi123 wrote: Given that x& = x^2 + 3, what is the value of integer k if there is a remainder of 3 when k& is divided by 4?
(1) 16 < k& < 37 (2) k is a factor of 24.
Can someone please explain this to me? Why are 19 and 28 the only possibility in statement 1? hi K&=K^2+3.. so k^2+3 when divided by 4 leaves a remainder of 3.. so K^2 must be divisible by 4... so k could be any even number 1)16<K&<37 \(16<K^2+3<37\).... \(K^2+3>16.....K^2>13...\) so K >3 and K is an integer \(K^2+3<37.....K^2<36..\) .so K<6 possible values of K are 4 and 5 but 5^2 is not div by 4, so our answer 4.. suff 2) K is a factor of 24 nothing much insuff A This would be correct if we were told that k is a positive integer. From (1) k could also be 4. (2) indirectly tells us that k must be positive, so the answer is C. Not a good question overall.
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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 04:37
Bunuel wrote: chetan2u wrote: nehalkapadi123 wrote: Given that x& = x^2 + 3, what is the value of integer k if there is a remainder of 3 when k& is divided by 4?
(1) 16 < k& < 37 (2) k is a factor of 24.
Can someone please explain this to me? Why are 19 and 28 the only possibility in statement 1? hi K&=K^2+3.. so k^2+3 when divided by 4 leaves a remainder of 3.. so K^2 must be divisible by 4... so k could be any even number 1)16 \(16\(K^2+3>16.....K^2>13...\) so K >3 and K is an integer \(K^2+3<37.....K^2<36..\) .so K<6 possible values of K are 4 and 5 but 5^2 is not div by 4, so our answer 4.. suff
2) K is a factor of 24 nothing much insuff
AThis would be correct if we were told that k is a positive integer. From (1) k could also be 4. (2) indirectly tells us that k must be positive, so the answer is C. Not a good question overall. yes I agree Bunuel.. and I doubt in GMAT a statement like " k is a factor of 24" would be given to give the info that k is positive..
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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 04:40



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 07:15
chetan2u wrote: nehalkapadi123 wrote: Given that x& = x^2 + 3, what is the value of integer k if there is a remainder of 3 when k& is divided by 4?
(1) 16 < k& < 37 (2) k is a factor of 24.
Can someone please explain this to me? Why are 19 and 28 the only possibility in statement 1? hi K&=K^2+3 .. so k^2+3 when divided by 4 leaves a remainder of 3.. so K^2 must be divisible by 4... so k could be any even number Can someone explain to me what is going on here? The question states "x& = x^2 + 3" so why do you conclude "K&=K^2+3"?? 1)16<K&<37 \(16<K^2+3<37\).... \(K^2+3>16.....K^2>13...\) so K >3 and K is an integer \(K^2+3<37.....K^2<36..\) .so K<6 possible values of K are 4 and 5 but 5^2 is not div by 4, so our answer 4.. suff 2) K is a factor of 24 nothing much insuff A



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 07:29
HarryAxel wrote: chetan2u wrote: nehalkapadi123 wrote: Given that x& = x^2 + 3, what is the value of integer k if there is a remainder of 3 when k& is divided by 4?
(1) 16 < k& < 37 (2) k is a factor of 24.
Can someone please explain this to me? Why are 19 and 28 the only possibility in statement 1? hi K&=K^2+3 .. so k^2+3 when divided by 4 leaves a remainder of 3.. so K^2 must be divisible by 4... so k could be any even number Can someone explain to me what is going on here? The question states "x& = x^2 + 3" so why do you conclude "K&=K^2+3"?? 1)16<K&<37 \(16<K^2+3<37\).... \(K^2+3>16.....K^2>13...\) so K >3 and K is an integer \(K^2+3<37.....K^2<36..\) .so K<6 possible values of K are 4 and 5 but 5^2 is not div by 4, so our answer 4.. suff 2) K is a factor of 24 nothing much insuff A Hi.. x isa variable and it is basically given to tell you about function '&' .. x can take any value as it is a variable... Ofcourse it could have been given as X& too..
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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 07:41
Ok but it is not stated that "&" is a function right? It could be a number so how can we tell?



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 23:15
HarryAxel wrote: Ok but it is not stated that "&" is a function right? It could be a number so how can we tell? I believe in GMAT it would be explicitly mentioned. Here its not explicitly mentioned, then we go by the conventions  what we generally follow. We use 'x', 'y', 'z' etc to represent variables (which are supposed to take various numerical values), but we dont use symbols like '&', '$', '#' etc to represent numbers  these are used for some specific purposes, one of which is to 'define a function'. Eg, here '&' has been defined as a function before which whenever you place any number, you have a result which is square of that placed number and then 3 added. So, 5& becomes = 5^2 + 3 = 28.



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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24 Jan 2018, 23:25



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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25 Jan 2018, 21:39
Just a quick question: If we are told K is a factor, couldn’t K be a negative number? Sent from my iPhone using GMAT Club Forum mobile app



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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25 Jan 2018, 21:40



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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a
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25 Jan 2018, 21:44
Thank you. A multiple could be negative, but NOT a factor. Clear!!!
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Re: Given that x& = x^2 + 3, what is the value of integer k if there is a &nbs
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