Forum Home > GMAT > Quantitative > Problem Solving (PS)
Events & Promotions
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
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Aug 2211:00 AM EDT
-11:59 PM EDT
More and more TTP students are earning impressive scores on the GMAT. Now is the perfect time to join the many GMAT students who made the switch to TTP and surpassed their wildest expectations on test day.
Aug 2910:00 PM IST
-11:30 PM IST
With brand new features like:AI-driven Planner tool, 850+ data Insights practice questions and GMAT Focus Edition Adaptive mock tests with ESR+ analysis and personal mentor support, our course is the most comprehensive course for GMAT Focus Edition.
Aug 3112:00 PM EDT
-03:00 PM EDT
Save 20% on Target Test Prep and Score in the 100th Percentile in GMAT Verbal! Our course uses techniques such as topical study and spaced repetition to maximize knowledge retention and make studying simple and fun.
Aug 3103:00 PM EDT
-11:59 PM EDT
For a limited time use code FALL20 to save on prep. Valid on Complete Course, Advanced Course, Bootcamp Course, Tutoring, and the Executive Assessment Course. This discount ends September 16th.
Sep 0212:01 AM PDT
-11:59 PM PDT
On Monday the 2nd, GMAT Club Tests will be Absolutely Free! Including all the Quizzes, Questions, and Tests. 12 AM - 11:59 PM PST- Sep 07
11:00 AM IST
-01:00 PM IST
Attend this session to learn how to Deconstruct arguments, Pre-Think Author’s Assumptions, and apply Negation Test.
Set S is a set of distinct positive integers. The standard deviation
[#permalink]
03 Jun 2019, 00:42
03 Jun 2019, 00:42
12
Bookmarks
Expert Reply
Show timer
00:00
A
B
C
D
E
Difficulty:
35%
(medium)
Question Stats:
68% (01:23) correct
32%
(01:28)
wrong
based on 158
sessions
Set S is a set of distinct positive integers. The standard deviation of Set S must increase if which of the following were to occur?
I. The smallest number is increased to become equal to the median.
II. The smallest number is increased to become larger than the current largest number.
III. The largest number is doubled.
A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
I. The smallest number is increased to become equal to the median.
II. The smallest number is increased to become larger than the current largest number.
III. The largest number is doubled.
A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
GMAT Club Legend
Joined: 12 Sep 2015
Posts: 6804
Given Kudos: 799
Location: Canada
Set S is a set of distinct positive integers. The standard deviation
[#permalink]
Updated on: 17 May 2021, 08:27
Updated on: 17 May 2021, 08:27
1
Kudos
4
Bookmarks
Expert Reply
Top Contributor
Bunuel wrote:
Set S is a set of distinct positive integers. The standard deviation of Set S must increase if which of the following were to occur?
I. The smallest number is increased to become equal to the median.
II. The smallest number is increased to become larger than the current largest number.
III. The largest number is doubled.
A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
I. The smallest number is increased to become equal to the median.
II. The smallest number is increased to become larger than the current largest number.
III. The largest number is doubled.
A. I only
B. II only
C. III only
D. I and III only
E. I, II and III
Nice question, Bunuel!!
The question asks "The standard deviation of Set S must increase if which of the following were to occur?"
So, if we can find a case in which the standard deviation does NOT increase, we can ELIMINATE it.
Let's check each statement....
I. The smallest number is increased to become equal to the median.
If we take the set {1, 18, 19} and increase the smallest number to equal the median, we get: {18, 18, 19}
This causes the standard deviation to DECREASE
So, statement I need not be true.
Scan the answer choices....ELIMINATE A, D and E
II. The smallest number is increased to become larger than the current largest number.
If we take the set {1, 900} and increase the smallest number to become larger than the current largest number., we get: {901, 900}
This causes the standard deviation to DECREASE
So, statement II need not be true.
Scan the answer choices....ELIMINATE B
By the process of elimination, the correct answer is C
Cheers,
Brent
RELATED VIDEO
Originally posted by BrentGMATPrepNow on 03 Jun 2019, 05:25.
Last edited by BrentGMATPrepNow on 17 May 2021, 08:27, edited 2 times in total.
Last edited by BrentGMATPrepNow on 17 May 2021, 08:27, edited 2 times in total.
General Discussion
Current Student
Joined: 08 Nov 2019
Posts: 55
Given Kudos: 1158
Location: United States (MN)
Concentration: Finance, International Business
GMAT 1: 580 Q47 V22
GMAT 2: 650 Q49 V29 (Online) 
GMAT 3: 680 Q49 V33
GMAT 4: 710 Q49 V38
GMAT 5: 730 Q50 V40
GPA: 3.29
WE:Architecture (Other)
Re: Set S is a set of distinct positive integers. The standard deviation
[#permalink]
02 May 2020, 19:05
02 May 2020, 19:05
1
Kudos
BrentGMATPrepNow
The questions says Set S is a set of distinct positive integers, your solution contains S having negative integers too.
Although the solution is correct, thought i would point that out
Thanks,
K
The questions says Set S is a set of distinct positive integers, your solution contains S having negative integers too.
Although the solution is correct, thought i would point that out
Thanks,
K
