# Statistics Examples

, , , , , , , ,

Step 1

The number of classes can be estimated using the rounded output of Sturges' rule, , where is the number of classes and is the number of items in the data set.

Step 2

Select classes for this example.

Step 3

Find the data range by subtracting the minimum data value from the maximum data value. In this case, the data range is .

Step 4

Find the class width by dividing the data range by the desired number of groups. In this case, .

Step 5

Round up to the nearest whole number. This will be the size of each group.

Step 6

Start with and create groups of size .

Step 7

Determine the class boundaries by subtracting from the lower class limit and by adding to the upper class limit.

Step 8

Draw a tally mark next to each class for each value that is contained within that class.

Step 9

Count the tally marks to determine the frequency of each class.

Step 10

The relative frequency of a data class is the percentage of data elements in that class. The relative frequency can be calculated using the formula , where is the absolute frequency and is the sum of all frequencies.

Step 11

is the sum of all frequencies. In this case, .

Step 12

The relative frequency can be calculated using the formula .

Step 13

Simplify the relative frequency column.

Step 14

Multiply every relative frequency by to get the percentage frequency.

Step 15

Simplify the Percentage column.