GRE Prep 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.
Apr 25Crafting an Impactful Resume: Balancing Detail with Brevity
10:00 AM EDT
-10:30 AM EDT
Showcase your achievements through impactful storytelling! Get ready for an LIVE session on April 25, Learn how to craft compelling narratives on your resume that resonate with admission committees.
Apr 26Get a Top GRE Score with Target Test Prep
12:00 PM EDT
-01:00 PM EDT
The Target Test Prep course represents a quantum leap forward in GRE preparation, a radical reinterpretation of the way that students should study. In fact, more and more Target Test Prep students are scoring 329 and above on the GRE.
In a certain sample of data, mean is 23 and standard deviati
[#permalink]
31 Dec 2021, 01:50
31 Dec 2021, 01:50
1
Bookmarks
00:00
Question Stats:
53% (00:34) correct
46% (00:34) wrong based on 13 sessions
Hide Show timer Statistics
In a certain sample of data, mean is 23 and standard deviation is 3.5. Which of the following values are less than 2 standard deviation from the mean?
A. 14
B. 15
C. 16
D. 17
E. 18
F. 28
Posted from my mobile device
A. 14
B. 15
C. 16
D. 17
E. 18
F. 28
Posted from my mobile device
Re: In a certain sample of data, mean is 23 and standard deviati
[#permalink]
31 Dec 2021, 09:35
31 Dec 2021, 09:35
Expert Reply
In my opinion the answers are wrong
The SD is 3.5 + 2 values = 5.5
The data point OR are above the mean + the 5.5 OR less than 23-5.5
So our values are OR above 28.5 OR less 17.5
So the answers should be from A >>> D
The SD is 3.5 + 2 values = 5.5
The data point OR are above the mean + the 5.5 OR less than 23-5.5
So our values are OR above 28.5 OR less 17.5
So the answers should be from A >>> D
Retired Moderator
Joined: 10 Apr 2015
Posts: 6218
Given Kudos: 136
In a certain sample of data, mean is 23 and standard deviati
[#permalink]
01 Jan 2022, 06:27
01 Jan 2022, 06:27
1
Sumukh19 wrote:
In a certain sample of data, mean is 23 and standard deviation is 3.5. Which of the following values are less than 2 standard deviation from the mean?
A. 14
B. 15
C. 16
D. 17
E. 18
F. 28
A. 14
B. 15
C. 16
D. 17
E. 18
F. 28
----------ASIDE----------------------------
A little extra background on standard deviations above and below the mean
If, for example, a set has a standard deviation of 4, then:
1 standard deviation = (1)(4) = 4
2 standard deviations = (2)(4) = 8
3 standard deviations = (3)(4) = 12
1.5 standard deviations = (1.5)(4) = 6
0.25 standard deviations = (0.25)(4) = 1
etc
------------------------------------------
So, if the mean of the sample is 23, and the standard deviation is 3.5, then:
2 standard deviations ABOVE the mean = 23 + 2(3.5) = 30
2 standard deviations BELOW the mean = 23 - 2(3.5) = 16
So, values that are LESS THAN 2 standard deviation from the mean, will be all values between (but not including) 16 and 30
Answer: D, E, F
