Name ________________________________________ Date __________________ Class __________________
Holt McDougal Mathematics
Chapter 7: Collecting, Displaying, and Analyzing Data Study Guide / Review for Mastery: Mean, Median, Mode, and Range
Measures of central tendency show what the middle of a data set looks like. The measures of central tendency are the mean, median, and mode.
Find the mean, median, mode, and range of 8, 3, 5, 4, 1, and 3.
List in order: 1, 3, 3, 4, 5, 8
Find the range, mean, median, and mode of each data set. 1. 6, 5, 3, 6, 8 2. 12, 15, 17, 9, 17
________5; 5.6; 6; 6 ____________________ _______ 8; 14; 15; 17 ___________________
3. 26, 35, 23, 27, 19, 23 4. 7, 6, 13, 16, 15, 9
________ 16; 25.5; 24.5; 23 _____________ _______ 10; 11; 11; no mode ___________
5. 42, 38, 45, 42, 43 6. 51, 62, 68, 55, 68, 62
________ 7; 42; 42; 42 _________________ ________ 17; 61; 62; 62 & 68 __________
7. Monthly Low Temperatures Month Jun. Jul. Aug. Sept. Oct.
Temperature (°F) 44 41 47 42 36
______________11 °F; 42 °F; 42 °F; no mode ____________________________________________
Find the mean. The mean is the sum of the values divided by the number of values in the data set. 1 + 3 + 3 + 4 + 5 + 8 = 24 24 ÷ 6 = 4 mean = 4
Find the range. Find the difference between the least and greatest values. 8 − 1 = 7 range = 7
Find the mode. The mode is the value that occurs most often. Sometimes there is no mode. mode = 3
Find the median. The median is the middle value. median = 3.5
Name ________________________________________ Date __________________ Class __________________
Holt McDougal Mathematics
Collecting, Displaying, and Analyzing Data SG/ RfM: Mean, Median, Mode, and Range (continued)
An outlier is a value that is much greater than or much less than the other values in a data set.
How does the outlier affect the mean, median, and mode of the data? 7, 9, 30, 9, 5, 6
Write the data in order and identify the outlier. 5, 6, 7, 9, 9, 30 outlier
USE THE EXAMPLE ABOVE TO ANSWER # 8 – 10 8.How does the outlier affect the mean? In general, it could increase or decrease the mean, for this example it increases by 3.8 9.How does the outlier affect the median? In general, it could increase or decrease the median, for this example it increases by 1
10. How does the outlier affect the mode? There is not effect.
To choose the measure of central tendency that best describes a set of data: • Choose the measure that is closest to the greatest number of
values in the data set, OR • If there is an outlier, think about how it affects the mean and the
median. Choose the measure that is affected least by the outlier.
Use the data set to answer the questions. 4, 6, 3, 6, 25, 3, 2 11. Is there an outlier? If so, what is it? _____ Yes; 25__ 12. How does the outlier affect the mean and the median?
__________________It increases the mean by 3 and the median by 0.5. _________________
13. Which measure of central tendency best describes the data? Explain your answer.
____________The median best describes the data set because it is least affected by the outlier _____________
With the Outlier Without the Outlier Find the mean. 7 + 9 + 30 + 9 + 5 + 6 = 66 66 ÷ 6 = 11 The mean is 11.
Find the mean. 7 + 9 + 9 + 5 + 6 = 36 36 ÷ 5 = 7.2 The mean is 7.2.
Find the median. 5, 6, 7, 9, 9, 30 7 + 9 = 16 16 ÷ 2 = 8 The median is 8.
Find the median. 5, 6, 7, 9, 9 The median is 7.
The mode is 9. The mode is 9.
