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 Author: Bunuel [ 27 Jan 2015, 07:43 ] Post subject: If x, y, and z are different positive integers, is x prime? If x, y, and z are different positive integers, is x prime?(1) xyz = 30(2) z < x < yKudos for a correct solution.

 Author: eddyki [ 27 Jan 2015, 08:52 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Quote:If x, y, and z are different positive integers, is x prime?(1) xyz = 30(2) z < x < yy=/=x=/=z but all >0 and int.(1) -> x could be 15 (z=1 and y=2) or 3 (z=5 and y=2) , its insuff.(2) -> 100<200<300 (no prime) or 1<2<3 (prime!) -> insuff.(1/2) -> we need 3 distinct factors of 30 -> 1/2/15 or 1/5/6 or 2/3/5 or 1/3/10 . every middle number is a prime, and since z is the smallest pos. int. and y the biggest pos. int., x is a prime number.C

 Author: chetan2u [ 27 Jan 2015, 09:07 ] Post subject: If x, y, and z are different positive integers, is x prime? ans C..1) it tells us that x is a divisor of 30..... x,y,z can be 1,2,3,5,6,10,152) insufficient..tells us x is middle value combined it tells us that x can be only 2,3,5 or 1,3,10, or 1,2,15 or 1,5,6 or .. so sufficient

 Author: gmat6nplus1 [ 27 Jan 2015, 14:03 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Bunuel wrote:If x, y, and z are different positive integers, is x prime?(1) xyz = 30(2) z < x < yKudos for a correct solution.1) case_1 xyz=3*2*5 answer=yes; case_2 xyz=1*2*15 answer no.Not sufficient2) Not sufficient1+2) x is every time going to be a prime number. SufficientAnswer C.

 Author: DesiGmat [ 28 Jan 2015, 01:33 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Here we go:x, y, and z are different positive integersSt1: xyz = 3030 = 2*3*5x = 2, y = 3 and z = 5 (Is X prime? -> true)x = 1, y = 6 and z = 5 (Is X prime? -> false)Not sufficientSt2: z < x < yClearly not sufficientCombining bothz = 2, x = 3, y = 5 (Is X prime? -> true)z = 1, x = 2, y = 15 (Is X prime? -> true)z = 1, x = 5, y = 6 (Is X prime? -> true)z = 1, x = 3, y = 10 (Is X prime? -> true)So C is the answer

 Author: santorasantu [ 28 Jan 2015, 07:19 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Bunuel wrote:If x, y, and z are different positive integers, is x prime?(1) xyz = 30(2) z < x < yKudos for a correct solution.Answer c:from stem: x,y and z are positive integersfrom 1: xyz = 30, prime factors of 30 are 1,2,3 and 5consider xyz = 2*3*5 = 30 => x is prime, consider xyz = 6*5*1 = 30, x is not prime, 2 answers NSFfrom 2: z

 Author: Derkus [ 30 Jan 2015, 23:30 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Quote:If x, y, and z are different positive integers, is x prime?(1) xyz = 30(2) z < x < y1) X*Y*Z = 30 so X*Y*Z must be two factors of 30 * 1X = 5, Y = 6, Z = 1: Yes X is primeX = 6, Y = 5, Z = 1: No X is not prime2) Z

 Author: Bunuel [ 02 Feb 2015, 02:49 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Bunuel wrote:If x, y, and z are different positive integers, is x prime?(1) xyz = 30(2) z < x < yKudos for a correct solution.VERITAS PREP OFFICIAL SOLUTION:Solution: CLet’s take statement (2) first: it gives us no values, so it’s INSUFFICIENT. Move on to statement (1). If three different positive integers have a product of 30, those integers must be one of the following sets:{ 1, 3, 10}; {2, 3, 5}; {1, 2, 15}; {1, 5, 6}. X could be prime or not prime; INSUFFICIENT. Combined, consider the four sets of possible integers. The median value is ALWAYS a prime number, so x must be prime. (C).

 Author: pacifist85 [ 07 Feb 2015, 05:20 ] Post subject: Re: If x, y, and z are different positive integers, is x prime?  xyz = 30 | NS because:2*3*5 = 30, x prime2*1*15 = 30, x prime15*1*2 = 30, x not prime z

 Author: shmba [ 22 Aug 2018, 20:53 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? chetan2u wrote:ans C..1) it tells us that x is a divisor of 30..... x,y,z can be 1,2,3,5,6,10,152) insufficient..tells us x is middle value combined it tells us that x can be only 2,3,5.. so sufficient1+2 combined: there should be 4 sets of combinations as stated in other posts. not just 2,3,5.

 Author: bumpbot [ 20 Dec 2022, 08:24 ] Post subject: Re: If x, y, and z are different positive integers, is x prime? Hello from the GMAT Club BumpBot!Thanks to another GMAT Club member, I have just discovered this valuable topic, yet it had no discussion for over a year. I am now bumping it up - doing my job. I think you may find it valuable (esp those replies with Kudos).Want to see all other topics I dig out? Follow me (click follow button on profile). You will receive a summary of all topics I bump in your profile area as well as via email.

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