Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 49496

Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
14 Oct 2014, 05:54
Question Stats:
87% (01:28) correct 13% (01:52) wrong based on 245 sessions
HideShow timer Statistics



Senior Manager
Joined: 13 Jun 2013
Posts: 277

Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
14 Oct 2014, 08:03
Bunuel wrote: Tough and Tricky questions: Statistics. Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y represents the product of all elements in set X and if 11Y is an even number, what is the range of set X? (A) 14 (B) 16 (C) 17 (D) 20 (E) 26 y = product of all elements in set X. now, y will be even if 2 is part of this set (k=2), else y will be odd. since we have, 11y as an even integer. therefore y must be even. (because 11 is odd, therefore the only way in which 11y can be even is when y is even.) thus elements in the set X are {2,3,11,7,17,19} and thus its range is 192=17



Intern
Joined: 18 Dec 2013
Posts: 28
Location: Canada
GPA: 2.84
WE: Project Management (Telecommunications)

Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
14 Oct 2014, 10:03
Bunuel wrote: Tough and Tricky questions: Statistics. Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y represents the product of all elements in set X and if 11Y is an even number, what is the range of set X? (A) 14 (B) 16 (C) 17 (D) 20 (E) 26 Since 11Y = Even therefore Y has to be EVEN since 11 is a odd integer (Even * Odd = Even)
Similarly, Y is the product of all integers in set X But all integers in Set X are odd except the unknown K and since X contains only prime numbers, K has to equal to 2... ( 2 is the only even prime number and the product of all prime numbers in set X has to be Even, Even * Odd = Even)
Since you know value of K you can calculate the range = Largest integer in the set minus Smallest integer in the set = 192 = 17
Answer is C



SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1834
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)

Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
14 Oct 2014, 19:47
Bunuel wrote: Tough and Tricky questions: Statistics. Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y represents the product of all elements in set X and if 11Y is an even number, what is the range of set X? (A) 14 (B) 16 (C) 17 (D) 20 (E) 26 Just observe the numbers given in the set {3, 11, 7, K, 17, 19} All numbers are odd & prime, so there product is also odd Given that 11y is even number (Again 11 is odd; so y has to be even) The only prime number which is even = 2So, for k = 2, range = 192 = 17 Answer = C
_________________
Kindly press "+1 Kudos" to appreciate



SVP
Status: The Best Or Nothing
Joined: 27 Dec 2012
Posts: 1834
Location: India
Concentration: General Management, Technology
WE: Information Technology (Computer Software)

Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
14 Oct 2014, 19:53
One more method: Just observe the OA (A) 14 (B) 16 (C) 17 (D) 20 (E) 26 Once we are convinced that k = 2, then Odd  Even = OddOnly option C fits in; all other options are Even suggesting that "k" would be ODD which is not the caseAnswer = C
_________________
Kindly press "+1 Kudos" to appreciate



VP
Status: It's near  I can see.
Joined: 13 Apr 2013
Posts: 1268
Location: India
Concentration: International Business, Operations
GPA: 3.01
WE: Engineering (Consulting)

Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
29 Jun 2018, 00:39
Bunuel wrote: Tough and Tricky questions: Statistics. Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y represents the product of all elements in set X and if 11Y is an even number, what is the range of set X? (A) 14 (B) 16 (C) 17 (D) 20 (E) 26 Bunuel, How would we know whether 11Y is a 3 digit integer with unit digit as Y or it is a product of 11 * Y?
_________________
"Do not watch clock; Do what it does. KEEP GOING."



Math Expert
Joined: 02 Sep 2009
Posts: 49496

Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
29 Jun 2018, 01:24
QZ wrote: Bunuel wrote: Tough and Tricky questions: Statistics. Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y represents the product of all elements in set X and if 11Y is an even number, what is the range of set X? (A) 14 (B) 16 (C) 17 (D) 20 (E) 26 Bunuel, How would we know whether 11Y is a 3 digit integer with unit digit as Y or it is a product of 11 * Y? If it were a threedigit number it would have been explicitly mentioned. 11y is 11*y, recall that only * sign could be omitted.
_________________
New to the Math Forum? Please read this: Ultimate GMAT Quantitative Megathread  All You Need for Quant  PLEASE READ AND FOLLOW: 12 Rules for Posting!!! Resources: GMAT Math Book  Triangles  Polygons  Coordinate Geometry  Factorials  Circles  Number Theory  Remainders; 8. Overlapping Sets  PDF of Math Book; 10. Remainders  GMAT Prep Software Analysis  SEVEN SAMURAI OF 2012 (BEST DISCUSSIONS)  Tricky questions from previous years.
Collection of Questions: PS: 1. Tough and Tricky questions; 2. Hard questions; 3. Hard questions part 2; 4. Standard deviation; 5. Tough Problem Solving Questions With Solutions; 6. Probability and Combinations Questions With Solutions; 7 Tough and tricky exponents and roots questions; 8 12 Easy Pieces (or not?); 9 Bakers' Dozen; 10 Algebra set. ,11 Mixed Questions, 12 Fresh Meat DS: 1. DS tough questions; 2. DS tough questions part 2; 3. DS tough questions part 3; 4. DS Standard deviation; 5. Inequalities; 6. 700+ GMAT Data Sufficiency Questions With Explanations; 7 Tough and tricky exponents and roots questions; 8 The Discreet Charm of the DS; 9 Devil's Dozen!!!; 10 Number Properties set., 11 New DS set.
What are GMAT Club Tests? Extrahard Quant Tests with Brilliant Analytics



Intern
Joined: 03 Jul 2016
Posts: 16

Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y
[#permalink]
Show Tags
29 Jun 2018, 22:25
The product of 11Y is an even number, therefore Y would be even and if you look at the prime numbers in set X all are odd, therefore K would be even to get 11Y even. So we need an even number in the set, which would be K, lowest number. As per equation: Range = Highest –Lowest (A) 14 (1914=5) (B) 16 (1916=3) (C) 17 (1917=2) (D) 20 (not possible, greater than 19) (E) 26 (not possible, greater than 19))




Re: Set X consists of prime numbers {3, 11, 7, K, 17, 19}. If integer Y &nbs
[#permalink]
29 Jun 2018, 22:25






