Page 315 - Algebra 1

Another way to analyze a set of numbers is by looking at its range. The range of a set of data is the difference between the greatest and least values in the data set.
Comparing Data
The table lists the total points teams scored in the two divisions of the All-Star Football League for the 2006 regular season.
Total Points Scored in the 2006 Regular Season
Does the North or the South have a greater range of points over the 2006 regular season?
SOLUTION
Find the range of values for each data set by determining the greatest and least values in each set and finding the difference between them.
North greatest value: 427; least value: 211 427 - 211 = 216 South greatest value: 492; least value: 168 492 - 168 = 324
Compare the ranges of the two data sets. 324 > 216
The data for the South has a greater range of values. Therefore, the values in this data set are more spread out than the values in the data set for the North.
Certain values in a data set can affect the measures of central tendency. An outlier is a data value that is much greater than or less than the other values in the data set.
Analyzing the Effects of an Outlier
The following data show the high temperatures (in degrees Fahrenheit) for the first fifteen days in July 2007 for Seattle, Washington.
75, 79, 81, 81, 84, 81, 81, 78, 76, 78, 89, 98, 81, 78, 86
a. Identify any outliers in the data set.
SOLUTION
Write the data in numeric order and observe any patterns.
75, 76, 78, 78, 78, 79, 81, 81, 81, 81, 81, 84, 86, 89, 98
The outlier value of 98 is much greater than the other values in the data set.
Example
2
North
398, 425, 355, 307, 427, 301, 282, 305, 413, 270, 292, 211, 335, 367, 298, 314
South
385, 316, 300, 260, 353, 373, 353, 238, 427, 324, 371, 267, 492, 331, 319, 168
Example
3
300 Saxon Algebra 1