6th Grade Math Textbook, Progress

Analyze Data

9-6

High temperatures of the last nine days were 2°C, 3°C, 1°C, 3°C, 5°C,

10°C, 4°C, 4°C, and 3°C. Kathy organizes the data in a line plot. A line plot

is a graph that uses Xs to show data on a number line.

Each X represents 1 day.

Clusters are places on the line plot where several Xs occur very

close together. There is a data cluster from 3°C to 4°C.


Gaps are large places on the line plot where no data occurs. A gap

exists between 5°C and 10°C.


Outliers are numbers set apart from the rest of the data. A set of data

may have no outliers or it may have one or more outliers. 10°C is an

outlier of the data set.

Outliers can affect the measures of central tendency of a data set.

Find the mean, median, and mode of the above data set.

Mean: 
 
3.9 mean 
3.9°C

Median:1, 2, 3, 3, 3 , 4, 4, 5, 10 median 
3°C

Mode:1, 2, 3 , 3 , 3 , 4, 4, 5, 10 mode 
3°C

Find the mean, median, and mode of the above data set withoutthe outlier.

Mean: 
 
3.1 mean 
3.1°C

Median:1, 2, 3 , 3 , 3 , 4, 4, 5 median 
 
3°C

Mode:1, 2, 3 , 3 , 3 , 4, 4, 5 mode 
3°C

When the outlier is not included in the data set, the mean decreases

by 0.8 degree. The median and the mode are not changed.

3 
 3

2

25

8

2 
 3 
 1 
 3 
 5 
 4 
 4 
 3

8

35

9

2 
 3 
 1 
 3 
 5 
 10 
 4 
 4 
 3

9

X

X

XXX X

1 2 3

X

X X

4

Temperature (°C)

High Temperatures

of the Last Nine Days

5 6 7 8 9 10

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