Chapter B.2, Problem 33E

a.

To determine

To find : The lower and upper quartiles of the data.

Answer to Problem 33E

The lower quartile is $11$ and the upper quartile is $17$ .

Explanation of Solution

Given: The given data is $23,15,14,23,13,14,13,20,12$ .

Calculation:

The given data is $23,15,14,23,13,14,13,20,12$ .

Data in asecending order

  $12,13,13,14,14,15,20,23,23$

This set has $9$ member .

The median of entire set is $14$ .

The median of the three number that are before $14$ is $13$ . So the lower quartile is $13$ .

The median of the four number that are after $14$ is $\frac{20+23}{2}=\frac{43}{2}=21.5$ . So the upper quartile is $21.5$ .

b.

To determine

To sketch:A box and whisker plot for the data without using graphing utility.

Answer to Problem 33E

Box and whisker plot is :

  

Explanation of Solution

Given: The given data is $23,15,14,23,13,14,13,20,12$ .

Calculation:

The given data is $23,15,14,23,13,14,13,20,12$ .

Data in asecending order

  $12,13,13,14,14,15,20,23,23$

This set has $9$ member .

The median of entire set is $14$ .

The median of the three number that are before $14$ is $13$ . So the lower quartile is $13$ .

The median of the four number that are after $14$ is $\frac{20+23}{2}=\frac{43}{2}=21.5$ . So the upper quartile is $21.5$ .

Box and whisker plot is :