Range and outliers

Range and outliers

In this section, we practice determining the range for data sets. Also, we identify outliers in data sets. A range is the positive difference between the largest and smallest values in a data set. An outlier is a value that is much smaller or larger than the other data values. It is possible for a data set to have one or more outliers. In this section, we are first given sets of data and asked to calculate the range of each set. Then, we are given word problems and asked to calculate the ranges and identify any outliers. Also, we are asked to use the mode and median of a given data set to determine the individual values in the set of data as well as the range of each set.

Lessons

• 1.
What is the range of each set of data?
a)
3, 8, 6, 12, 10, 14, 9, 4

b)
-4, 3, -8, 9, 11, -11, 0

c)
41, 23, 54, 21, 37, 33, 19, 22, 17

• 2.
Kate was given a Nancy Drew mystery computer game for her birthday. The following times indicate how long it took her to complete the game the first 5 times she did it:

10 hours, 6 hours, 5 hours, 3 hours, 2 hours
a)
What is the range?

b)
Which time may be an outlier?

c)
If the outlier is removed, what is the new range?

• 3.
Four athletes completed a 50m freestyle race at a swim competition.
• The fastest time was 28 seconds.
• The mode was 31 seconds.
• The mean was 30 seconds.
a)
What were the finishing times for the 4 athletes?

b)
What is the range of times?