Quartile
How to find the quartiles (Q1, Q2, Q3) of the given data: definition, 2 examples, and their solutions.
Definition
The quartiles (Q1, Q2, Q3) are the numbers
that divide the data into 4 parts.
Example
First find Q2.
Q2 is the median of the data.
The median of the data is
this 6.
So Q2 = 6.
Next, see the values
on the left side of Q2.
Q1 is the median of these values.
The median is
4.
So Q1 = 4.
Next, see the values
on the right side of Q2.
Q3 is the median of these values.
The median is
this 7.
So Q3 = 7.
Write Q1, Q2, and Q3.
So
Q1 = 4
Q2 = 6
Q3 = 7
is the answer.
Example
First find Q2.
Q2 is the median of the data.
The median of the data is
the mean of 6 and this 7.
The mean of 6 and 7 is
[6 + 7]/2 = 6.5.
So Q2 = 6.5.
Next, see the values
on the left side of Q2.
The value 6
is in the left side of Q2 = 6.5.
So include the value 6.
Q1 is the median of these values.
The median is
4.
So Q1 = 4.
Next, see the values
on the left side of Q3.
This value 7
is in the right side of Q2 = 6.5.
So include this value 7.
Q3 is the median of these values.
The median is
this 7.
So Q3 = 7.
Write Q1, Q2, and Q3.
So
Q1 = 4
Q2 = 6.5
Q3 = 7
is the answer.