Measures of Spread

What is the formula for calculating the range of a data set?

• Q3 - Q1

• Mean - Median

• Maximum - Minimum

• Q1 + Q3

• 2

• 3

• 4

• 5

• It increases

• It stays the same

• It decreases

Use the 1.5 IQR rule to determine if there are any outliers for the following numbers: 84, 88, 72, 74, 98, 16, 94

• 16 is an outlier.

• 33 is an outlier.

• 98 is an outlier.

• There are no outliers.

• 94 is an outlier.

• The data has an outlier, 3.05 inches.

• The standard deviation is 0.9114

• The IQR is 0.961

• The median is 5.355

• The data has no outliers

The golf coach wants to compare the students’ scores at the end of the season with their scores at the beginning of the season. What is the mean and standard deviation of the data at the beginning of the season?

• Mean: 80; Standard Deviation: 2.6

• Mean: 80; Standard Deviation: 3.1

• Mean: 82; Standard Deviation: 2.5

• Mean: 82; Standard Deviation: 2.8

The golf coach wants to compare the students’ scores at the end of the season with their scores at the beginning of the season. What is the mean and standard deviation of the data at the end of the season?

• Mean: 79;

  Standard Deviation: 2.5

• Mean: 79;

  Standard Deviation: 2.8

• Mean: 81;

  Standard Deviation: 2.6

• Mean: 81;

  Standard Deviation: 2.2

The following dotplot shows the number of e-mails that you deleted each day. Each dot represents a different day. How many outliers are there?

• 0

• 1

• 2

• 3

• 0%

• 25%

• 50%

• 75%

• 100%

Which number is an outlier?

• Only 50

• Only 79

• Both 50 and 79

• No outliers