The range of set A is r. If a number with a value equal to r : Quant Question Archive [LOCKED]
Check GMAT Club Decision Tracker for the Latest School Decision Releases http://gmatclub.com/AppTrack

 It is currently 23 Jan 2017, 21:19

### 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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# The range of set A is r. If a number with a value equal to r

Author Message
VP
Joined: 22 Nov 2007
Posts: 1092
Followers: 8

Kudos [?]: 489 [0], given: 0

The range of set A is r. If a number with a value equal to r [#permalink]

### Show Tags

12 Mar 2008, 10:18
1
This post was
BOOKMARKED
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

The range of set A is r. If a number with a value equal to r is added to set A,
will the range of set A increase?

(1) All numbers in the set are positive
(2) The mean of the new set is smaller than R
Director
Joined: 10 Sep 2007
Posts: 947
Followers: 8

Kudos [?]: 287 [0], given: 0

### Show Tags

12 Mar 2008, 19:02
Range of a set is = Maximum Value in set - Minimum Value in set

Statement 1:
Tells us that all the numbers in set are +ve. So in this case Maximum Value - Minimum value will result in a number that is lesser than Maximum value of range but more than minimum value. Any number added to set that is not changing maximum value or minimum value will not change the range of set.
So this alone can answer the question.

Statement 2:
Tells us that the mean of the new set is smaller than R. What about the mean of old set, was that smaller than R as well. Moreover it may also lead to think -ve numbers are involved. So this alone is not sufficient.

Senior Manager
Joined: 15 Aug 2007
Posts: 252
Schools: Chicago Booth
Followers: 1

Kudos [?]: 69 [0], given: 0

### Show Tags

12 Mar 2008, 21:13
I am getting C

Statement 1:
took two random example 6,7,10 and 3,5,6,7 - in the first case range was increased and in the later case range remained same. so insufficient.

Statement 2:
Got different results for positive numbers and a combination of positive and negative. (eg, 2,6,9 and -2,-1,1)

Combined - for positive numbers, given the second condition, always got same range. Somehow I am not confident though because this is all driven by examples. But I would go with C in GMAT.
VP
Joined: 22 Nov 2007
Posts: 1092
Followers: 8

Kudos [?]: 489 [0], given: 0

### Show Tags

12 Mar 2008, 21:46
sreehari wrote:
I am getting C

Statement 1:
took two random example 6,7,10 and 3,5,6,7 - in the first case range was increased and in the later case range remained same. so insufficient.

Statement 2:
Got different results for positive numbers and a combination of positive and negative. (eg, 2,6,9 and -2,-1,1)

Combined - for positive numbers, given the second condition, always got same range. Somehow I am not confident though because this is all driven by examples. But I would go with C in GMAT.

OA is C in fact. would you mind showing your reasoning with numerical examples?
Senior Manager
Joined: 15 Aug 2007
Posts: 252
Schools: Chicago Booth
Followers: 1

Kudos [?]: 69 [0], given: 0

### Show Tags

13 Mar 2008, 06:50
[quote="marcodonzelli]
OA is C in fact. would you mind showing your reasoning with numerical examples?[/quote]

I picked the series in such a way that when range is added to the series, in one case it increases the range, and in another case it keeps it same.

6,7,10 becomes 4, 6,7,10 - increases the range from 4 to 6
3,5,6,7 becomes - 3,4,5,6,7 - doesn't change the range (4)

for the second statement though it wasn't easy - had to try few different series to come up with ones that satisfy the condition.
VP
Joined: 22 Nov 2007
Posts: 1092
Followers: 8

Kudos [?]: 489 [0], given: 0

### Show Tags

13 Mar 2008, 23:25
sreehari wrote:
[

for example, the second statement could be:

-4 and -6, range 2, which added would give a range of 8, higher than before and mean 8/3, less than new R

anyway:

1 and 4, range 3, new mean 8/3 and range is 3 but range is always the same.

only C is suff, since with positive numbers and the new mean less than the new range , the range would not increase.

how is it possible to answer this one in 2 mins?
CEO
Joined: 17 Nov 2007
Posts: 3589
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Followers: 550

Kudos [?]: 3565 [0], given: 360

### Show Tags

14 Mar 2008, 04:33
C

there are three options:

A) -------0-----------------r---------------[AAAAAAAAAAAAA] the range of set A increases
B) -------0-[AAAAAAAAAArA]------------------------------- the range of set A does not increase
C) --[AA0AAAAAAAAA]--r------------------------------------ the range of set A increases

1. A and B survive. insuff.
2. B and C survive. insuff.
1.&2 only B survives. suff.
_________________

HOT! GMAT TOOLKIT 2 (iOS) / GMAT TOOLKIT (Android) - The OFFICIAL GMAT CLUB PREP APP, a must-have app especially if you aim at 700+ | PrepGame

Re: gprep stats   [#permalink] 14 Mar 2008, 04:33
Display posts from previous: Sort by

# The range of set A is r. If a number with a value equal to r

 Powered by phpBB © phpBB Group and phpBB SEO Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.