initial class boundary of 1.5
ending class boundary of 13.5
Number of classes: 6
Class width: Subtract initial class boundary from ending class boundary and divide the result into the number of classes:
Classes:
1.5 - 3.5
3.5 - 5.5
5.5 - 7.5
7.5 - 9.5
9.5 - 11.5
11.5 - 13.5
Order the given data to find easily the frequency of each class:
Then, you get frequencies of:
1.5 - 3.5: 4
3.5 - 5.5: 2
5.5 - 7.5: 2
7.5 - 9.5: 2
9.5 - 11.5: 6
11.5 - 13.5: 3
And you get the next histogram: