February 20, 2019 February 20, 2019 08:00 PM EST 09:00 PM EST Strategies and techniques for approaching featured GMAT topics. Wednesday, February 20th at 8 PM EST February 21, 2019 February 21, 2019 10:00 PM PST 11:00 PM PST Kick off your 2019 GMAT prep with a free 7day boot camp that includes free online lessons, webinars, and a full GMAT course access. Limited for the first 99 registrants! Feb. 21st until the 27th.
Author 
Message 
TAGS:

Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 52971

Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
15 Dec 2014, 08:19
Question Stats:
88% (00:51) correct 12% (01:41) wrong based on 176 sessions
HideShow timer Statistics



Manager
Joined: 10 Sep 2014
Posts: 96

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
15 Dec 2014, 09:24
x+y > 20?
statement 1: sufficient (2x+2y) / 2 = 48. multiply both sides by 2 to remove the fraction, then divide both sides by 2 to remove coefficients of x and y to leave us with x+y=48. The average of x and y will always be 24 for any 2 values according to this statement.
statement 2: insufficient x=1, y=3, average is 2, less than 20 x=100, y=300, average is 200, greater than 20
Answer A!



Manager
Joined: 21 Aug 2010
Posts: 174
Location: United States

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
16 Dec 2014, 22:50
Bunuel wrote: Tough and Tricky questions: Number Properties. Is the average (arithmetic mean) of x and y greater than 20? (1) The average (arithmetic mean) of 2x and 2y is 48. (2) x = 3y Kudos for a correct solution.1) (2X+2Y)/2 = 48=> (x+y)/2 = 24 sufficient 2) Insufficient as the value cannot be calculated using the onformation given Ans A
_________________




Math Expert
Joined: 02 Sep 2009
Posts: 52971

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
23 Dec 2014, 05:49



Senior Manager
Status: Math is psychological
Joined: 07 Apr 2014
Posts: 415
Location: Netherlands
GMAT Date: 02112015
WE: Psychology and Counseling (Other)

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
08 Feb 2015, 02:29
Hello,
[1] is pretty much straight forward. [2] i guess also is not too complicated, but as I didn't see what I did I am posting it, just in case it was wrong..
So, we are looking for (x+y)/2 and whether it is more than 20. Substituting x for 3y in the equation above we get:
(3y+y)/2 = 4y/2 = 2y. We don't know what y is, so insufficient. Leading to ANS A.



Current Student
Joined: 19 May 2016
Posts: 29
Location: United States
Concentration: Strategy, Human Resources
GMAT 1: 710 Q46 V41 GMAT 2: 730 Q49 V41 GMAT 3: 680 Q46 V37
WE: Operations (Manufacturing)

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
21 Jul 2016, 11:22
Bunuel wrote: Tough and Tricky questions: Number Properties. Is the average (arithmetic mean) of x and y greater than 20? (1) The average (arithmetic mean) of 2x and 2y is 48. (2) x = 3y Kudos for a correct solution.When I was solving this problem, I got statement one right, but when I got to statement 2, I got Y>10, and X>30, and assumed that X+Y must then be greater than 40. Am I missing something? Please help me clarify. Thank you!



Math Expert
Joined: 02 Sep 2009
Posts: 52971

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
21 Jul 2016, 12:55



Current Student
Joined: 19 May 2016
Posts: 29
Location: United States
Concentration: Strategy, Human Resources
GMAT 1: 710 Q46 V41 GMAT 2: 730 Q49 V41 GMAT 3: 680 Q46 V37
WE: Operations (Manufacturing)

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
21 Jul 2016, 13:24
Bunuel wrote: toby001 wrote: Bunuel wrote: Tough and Tricky questions: Number Properties. Is the average (arithmetic mean) of x and y greater than 20? (1) The average (arithmetic mean) of 2x and 2y is 48. (2) x = 3y Kudos for a correct solution.When I was solving this problem, I got statement one right, but when I got to statement 2, I got Y>10, and X>30, and assumed that X+Y must then be greater than 40. Am I missing something? Please help me clarify. Thank you! For (2) we only know that x = 3y. How did you get that y > 10 and x > 30 from that? I'm starting to feel like I did something stupid here, or I'm reading somewthing wrong. Anyway, Using the inequality and the eauation given in (2), I solved for X and Y.



Math Expert
Joined: 02 Sep 2009
Posts: 52971

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
21 Jul 2016, 20:50
toby001 wrote: Bunuel wrote: toby001 wrote: Tough and Tricky questions: Number Properties. Is the average (arithmetic mean) of x and y greater than 20? (1) The average (arithmetic mean) of 2x and 2y is 48. (2) x = 3y When I was solving this problem, I got statement one right, but when I got to statement 2, I got Y>10, and X>30, and assumed that X+Y must then be greater than 40. Am I missing something? Please help me clarify. Thank you! For (2) we only know that x = 3y. How did you get that y > 10 and x > 30 from that? I'm starting to feel like I did something stupid here, or I'm reading somewthing wrong. Anyway, Using the inequality and the eauation given in (2), I solved for X and Y. From the stem we have a question: Is the average (arithmetic mean) of x and y greater than 20? Is (x + y)/2 > 20? This is not given to be true, this is the question we need to answer.
_________________
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



Current Student
Joined: 12 Aug 2015
Posts: 2621

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
21 Dec 2016, 16:00



NonHuman User
Joined: 09 Sep 2013
Posts: 9856

Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
Show Tags
27 Sep 2018, 07:33
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.
_________________
GMAT Books  GMAT Club Tests  Best Prices on GMAT Courses  GMAT Mobile App  Math Resources  Verbal Resources




Re: Is the average (arithmetic mean) of x and y greater than 20?
[#permalink]
27 Sep 2018, 07:33






