Summer is Coming! Join the Game of Timers Competition to Win Epic Prizes. Registration is Open. Game starts Mon July 1st.

 It is currently 19 Jul 2019, 16:05

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# For the list of numbers above, what is the range?

Author Message
TAGS:

### Hide Tags

Math Expert
Joined: 02 Sep 2009
Posts: 56300
For the list of numbers above, what is the range?  [#permalink]

### Show Tags

20 May 2017, 05:25
2
5
00:00

Difficulty:

45% (medium)

Question Stats:

61% (01:15) correct 39% (01:03) wrong based on 178 sessions

### HideShow timer Statistics

-10, 3, 5, x, y

For the list of numbers above, what is the range?

(1) The list of numbers has exactly two modes.

(2) x does not equal y

_________________
CEO
Joined: 12 Sep 2015
Posts: 3851
Re: For the list of numbers above, what is the range?  [#permalink]

### Show Tags

20 May 2017, 05:50
Top Contributor
1
Bunuel wrote:
-10, 3, 5, x, y

For the list of numbers above, what is the range?

(1) The list of numbers has exactly two modes.

(2) x does not equal y

Target question: What is the range?

Given: Set = {-10, 3, 5, x, y}

Statement 1: The list of numbers has exactly two modes.
This tells us that x must equal one of -10, 3, 5, and y must also equal one of -10, 3, 5, BUT X AND Y ARE DIFFERENT VALUES
For example, it COULD be that x = -10 and y = 3, in which case the set = {-10, 3, 5, -10, 3}. In this case, the modes are -10 and 3, and the range = 5 - (-10) =15
Or it COULD be that x = 5 and y = -10, in which case the set = {-10, 3, 5, 5, -10}. In this case, the modes are 5 and -10, and the range = 5 - (-10) =15
Or it COULD be that x = 3 and y = 5, in which case the set = {-10, 3, 5, 3, 5}. In this case, the modes are 3 and 5, and the range = 5 - (-10) =15
etc.
Since x and y are equal to the values -10, 3, and 5, the range will ALWAYS equal 5 - (-10) =15
Since we can answer the target question with certainty, statement 1 is SUFFICIENT

Statement 2: x does not equal y
There are several values of x and y that satisfy statement 2. Here are two:
Case a: x = -10 and y = 3, in which case the set = {-10, 3, 5, -10, 3}. In this case, the range = 5 - (-10) =15
Case b: x = -100 and y = 200, in which case the set = {-10, 3, 5, -100, 200}. In this case, the range = 200 - (-100) =300
Since we cannot answer the target question with certainty, statement 2 is NOT SUFFICIENT

RELATED VIDEO

_________________
Test confidently with gmatprepnow.com
Manager
Joined: 24 Dec 2016
Posts: 96
Location: India
Concentration: Finance, General Management
WE: Information Technology (Computer Software)
Re: For the list of numbers above, what is the range?  [#permalink]

### Show Tags

29 May 2017, 23:55
Bunuel wrote:
-10, 3, 5, x, y

For the list of numbers above, what is the range?

(1) The list of numbers has exactly two modes.

(2) x does not equal y

Stmt 1 : There are exactly 2 modes. As there are a total of 5 numbers, 2 of those are repeated twice and 1 of them is present once.

Range is basically the diff. between the max and min. value. Min. out of the 3 mentioned is -10 and max. is 5.
Whatever be the mode, range would be the same as the values are fixed.

Lets take a few scenarios-

Case 1 : Let -10 and 3 be the modes.
Set = {-10, -10, 3, 3, 5} --> Range = 15

Case 2 : Let -10 and 5 be the modes.
Set = {-10, -10, 3, 5, 5} --> Range = 15

Case 3 : Let 3 and 5 be the modes.
Set = { -10, 3, 3, 5, 5} --> Range = 15

Sufficient.

Stmt 2 : x != y
Clearly insufficient as doesnt give any data points on the values of x and y.

Option A.
Intern
Joined: 03 Nov 2016
Posts: 16
GMAT 1: 620 Q47 V30
GMAT 2: 710 Q48 V39
Re: For the list of numbers above, what is the range?  [#permalink]

### Show Tags

05 Jun 2017, 22:38
My approach is bit simple.

given -10, 3, 5, x, y.
St 1: the list has two modes that means X and Y can take any of the three values from the list but not an outside number. In any case the least no will remain -10 and highest number will remain 5. So, range will be the same. Hence, Sufficient. Possible Ans A or D
St 2: X !=Y Clearly insufficient.
Senior Manager
Joined: 13 Oct 2016
Posts: 274
GMAT 1: 600 Q44 V28
Re: -10, 3, 5, x, y - For the list of numbers above, what is the range?  [#permalink]

### Show Tags

09 Jul 2017, 08:58
could some one provide me an explanation for the answer ? i got the answer as E.
_________________
_______________________________________________
If you appreciate the post then please click +1Kudos
Retired Moderator
Joined: 19 Mar 2014
Posts: 929
Location: India
Concentration: Finance, Entrepreneurship
GPA: 3.5
Re: -10, 3, 5, x, y - For the list of numbers above, what is the range?  [#permalink]

### Show Tags

09 Jul 2017, 09:02
OFFICIAL EXPLANATION By Veritas

The correct answer is A. In order for this list of numbers to have exactly two modes (as statement 1 states), when the given information includes three, unique, known values and two variables, x and y must each match a different known number. That would mean that each of two known values appears exactly twice, making those two values the modes.

If x and y were each unique values that did not match a value already known, there would be no mode to the set. If x equaled y but neither matched a value already known, then that x and y would form the single mode, and there would not be a second.

So in order for statement 1 to be true, x and y must match already known values. Bringing that back to the exact question, that would mean that the list only includes the values -10, 3, and 5 (with duplicates of two of those three), so the range would have to be 5 - (-10) = 15.

Statement 2 is not sufficient: leaving out the information from statement 1, statement 2 still allows x and y to be any value (as long as they don't match each other), so you cannot put a limit on the least or greatest value, and the range still has infinite potential values.
_________________
"Nothing in this world can take the place of persistence. Talent will not: nothing is more common than unsuccessful men with talent. Genius will not; unrewarded genius is almost a proverb. Education will not: the world is full of educated derelicts. Persistence and determination alone are omnipotent."

Best AWA Template: https://gmatclub.com/forum/how-to-get-6-0-awa-my-guide-64327.html#p470475
Manager
Joined: 23 May 2017
Posts: 236
Concentration: Finance, Accounting
WE: Programming (Energy and Utilities)
Re: -10, 3, 5, x, y - For the list of numbers above, what is the range?  [#permalink]

### Show Tags

09 Jul 2017, 09:07
2
Attachment:

FullSizeRender (10).jpg [ 89.76 KiB | Viewed 1859 times ]

A
_________________
If you like the post, please award me Kudos!! It motivates me
Manager
Joined: 24 Sep 2018
Posts: 140
For the list of numbers above, what is the range?  [#permalink]

### Show Tags

26 Sep 2018, 10:01
The correct answer is A. In order for this list of numbers to have exactly two modes (as statement 1 states), when the given information includes three, unique, known values and two variables, x and y must each match a different known number. That would mean that each of two known values appears exactly twice, making those two values the modes.

If x and y were each unique values that did not match a value already known, there would be no mode to the set. If x equaled y but neither matched a value already known, then that x and y would form the single mode, and there would not be a second.

Quote:
So in order for statement 1 to be true, x and y must match already known values. Bringing that back to the exact question, that would mean that the list only includes the values -10, 3, and 5 (with duplicates of two of those three), so the range would have to be 5 - (-10) = 15.

Quote:
Statement 2 is not sufficient: leaving out the information from statement 1, statement 2 still allows x and y to be any value (as long as they don't match each other), so you cannot put a limit on the least or greatest value, and the range still has infinite potential values.

Quote:
Take Away: Adding the same value to the set never changes the range

_________________
Please award kudos, If this post helped you in someway.
For the list of numbers above, what is the range?   [#permalink] 26 Sep 2018, 10:01
Display posts from previous: Sort by