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.
First quartile and 3rd quartile
[#permalink]
08 Oct 2020, 01:38
08 Oct 2020, 01:38
1
Bookmarks
00:00
Question Stats:
100% (02:04) correct
0% (00:00) wrong based on 2 sessions
Hide Show timer Statistics
If set A is ( 3, 7, 8, 5, 14, 14, 21, 15, 18, 14)
What is the First quartile and 3rd quartile?
My pivotal question, we have median = 14, so do we exclude it when finding Q1 and Q3?
3 5 7 8 : Q1= 12/2=6
15 18 21: Q3= 18
or
3 5 7 8 14 | 14 14 15 18 21
and Q1= 7 Q3= 15
The source of question is my mind.
What is the First quartile and 3rd quartile?
My pivotal question, we have median = 14, so do we exclude it when finding Q1 and Q3?
3 5 7 8 : Q1= 12/2=6
15 18 21: Q3= 18
or
3 5 7 8 14 | 14 14 15 18 21
and Q1= 7 Q3= 15
The source of question is my mind.
Re: First quartile and 3rd quartile
[#permalink]
21 Oct 2020, 14:03
21 Oct 2020, 14:03
Asmakan wrote:
If set A is ( 3, 7, 8, 5, 14, 14, 21, 15, 18, 14)
What is the First quartile and 3rd quartile?
My pivotal question, we have median = 14, so do we exclude it when finding Q1 and Q3?
3 5 7 8 : Q1= 12/2=6
15 18 21: Q3= 18
or
3 5 7 8 14 | 14 14 15 18 21
and Q1= 7 Q3= 15
The source of question is my mind.
What is the First quartile and 3rd quartile?
My pivotal question, we have median = 14, so do we exclude it when finding Q1 and Q3?
3 5 7 8 : Q1= 12/2=6
15 18 21: Q3= 18
or
3 5 7 8 14 | 14 14 15 18 21
and Q1= 7 Q3= 15
The source of question is my mind.
To find the first and third quartile. we need to find the median. We have 10 elements, so the median will be the average of the 5th and 6th element, which is 14.
The median divide the set in two groups:
1: 3,5,7,8,14
2: 14,14,15,18,21
The first quartile will be the median of the first group, which is 7.
The third quartile will be the median of the third group, which is 15.
Moderator
Joined: 02 Jan 2020
Status:GRE Quant Tutor
Posts: 1111
Given Kudos: 9
Location: India
Concentration: General Management
Schools: XLRI Jamshedpur, India - Class of 2014
GMAT 1: 700 Q51 V31
GPA: 2.8
WE:Engineering (Computer Software)
First quartile and 3rd quartile
[#permalink]
19 Oct 2022, 09:17
19 Oct 2022, 09:17
1
Given that set A is ( 3, 7, 8, 5, 14, 14, 21, 15, 18, 14) and we need to find What is the First quartile and 3rd quartile?
To solve this lets arrange the set in ascending order. We get
3, 5, 7, 8, 14, 14, 14, 15, 18, 21 => 10 numbers
Median of the set will be the mean of middle two terms = \(\frac{14 + 14}{ 2}\) = 14
(Watch this Video to know more about Medians and Statistics)
Now, the Median divides the set into two parts
First half -> 3, 5, 7, 8, 14
Second Half -> 14, 14, 15, 18, 21
First Quartile or \(Q_1\) is the Median of the first half = Middle value = 7
Third Quartile or \(Q_3\) is the Median of the second half = Middle value = 15
So, Answer will be 7 and 15.
Hope it helps!
Asmakan: In case of odd number of values we keep the middle value as the Median or \(Q_2\) and Ignore the Median value while dividing the set into first and second half.
Ex: If the set is as follows:
1, 2, 3, 4, 5, 6, 7
Then \(Q_2\) or Median = 4
First Half = 1, 2, 3 => \(Q_1\) = 2
Second Half = 5, 6, 7 => \(Q_3\) = 6
Watch the following video to learn the Basics of Box and Whisker Plot
To solve this lets arrange the set in ascending order. We get
3, 5, 7, 8, 14, 14, 14, 15, 18, 21 => 10 numbers
Median of the set will be the mean of middle two terms = \(\frac{14 + 14}{ 2}\) = 14
(Watch this Video to know more about Medians and Statistics)
Now, the Median divides the set into two parts
First half -> 3, 5, 7, 8, 14
Second Half -> 14, 14, 15, 18, 21
First Quartile or \(Q_1\) is the Median of the first half = Middle value = 7
Third Quartile or \(Q_3\) is the Median of the second half = Middle value = 15
So, Answer will be 7 and 15.
Hope it helps!
Asmakan: In case of odd number of values we keep the middle value as the Median or \(Q_2\) and Ignore the Median value while dividing the set into first and second half.
Ex: If the set is as follows:
1, 2, 3, 4, 5, 6, 7
Then \(Q_2\) or Median = 4
First Half = 1, 2, 3 => \(Q_1\) = 2
Second Half = 5, 6, 7 => \(Q_3\) = 6
Watch the following video to learn the Basics of Box and Whisker Plot
