We are given the following data
17 18 12 9 14 14 13 1 14 14 6 7 14 1 3 12 17 19 13 0
We are told that we will use 5 classes. So, first, we will determine the spread of the data (max -min) and divide it by 5 to determine the lenght of each class. We can see that the minimum data point is 0 and the maximum data point is 19. So the data spread is 19-0 =0. We will use 5 classes, so each class should have a lenght of 19/5 = 3.8. Since all our datapoints are integers, we can use a class length of 4.
So in this case our classes will have the following range
0-3
4-7
8 - 11
12 -15
16-20
Now, to determine the relative frequency, we just count the number of data points that are in each class. So we get
class Frequency
0-3
4-7
8 - 11
12 -15
16-20
