To construct the histogram, the first step is to construct a frequency table using the data set.
First, let's determine class intervals. Starting with 0 create class intervals with an amplitude of 50 units, following the scale used in the graph.
Add the amplitude to the initial value to determine the upper bound of the first interval:
[tex]0+50=50[/tex]
The first interval is [0,50)
For the second interval, the lower bound will be the upper bound of the previous interval. Add the amplitude to determine the upper bound of the interval:
[tex]50+50=100[/tex]
The second interval is [50,100)
Repeat to create the following interval until you reach 250:
Third interval
[tex]100+50=150[/tex]
The interval is [100,150)
Fourth interval
[tex]150+50=200[/tex]
The interval is [150,200)
Fifth interval
[tex]200+50=250[/tex]
The interval is [200,250)
Now you can construct the table:
Order the data set from least to greatest and count how many observations belong to each interval:
23, 78, 130, 147, 156, 177, 184, 213
To the first interval correspond one observation: 23
To the second interval corresponds one observation: 78
To the third interval correspond two observations: 130, 147
To the fourth interval correspond 3 observations: 156, 177, 184
To the fifth interval corresponds 1 observation: 213
Complete the table
Now you can construct the histogram, in the x-axis you have to write the intervals (lengths), and in the y-axis, you have to write the frequencies (number of drives):
