Document Sample

Name: __________________________________________________________ Calculating the Mean, Median, and Mode The mean, median, and mode are single numbers that help describe how the individual scores in a data set are distributed in value. A data set consists of the observations for some variable is referred to as raw data or ungrouped data. The Mean The arithmetic mean is another name for the average of a set of scores. The mean can be found by dividing the sum of the scores by the number of scores. This best used when there are few outliers. For example, the mean of 5, 8, 2, and 1 can be found by first adding up the numbers. 5 + 8 + 2 + 1 = 16. The mean is then found by taking this sum and dividing it by the number of scores, called the count. Our data set 5, 8, 2, and 1 has a count of 4 hence the mean is 16 ÷ 4 = 4. The Median The median of a set of data values is the middle value once the data set has been arranged in order of its values. This is best used when there are outliers at both ends of the data or when the range is to great to establish a mode To find the mean of 2, 9, and 1, first arrange in order: 1, 2, 9. The median is the middle number or 2. If you have an even number of values such as 1, 2, 5, and 8, the median is the average of the two middle numbers. The median for 1, 2, 6, and 8 is the average of 2 and 6 = 4. The Mode The mode of a set of data values is the number in the set that appears most frequently. If no number appears more than once, then the data set has no mode. Or if it has multiple modes and not a great deal of data, true multiple modes are rare. It is best used when it is clustered and has outliers in the data. For example, the number 5 appears three times in 1, 2, 5, 5, 5, 8, 8, 9. Since the number 5 appears the most times, it is the mode. A set of numbers that can have more than one mode, as long as the number appears more than once. In the data set 1, 2, 2, 3, 3, 4, 5. The mode is 2 and 3. We also can say that this data set is bimodal. The Outlier A piece of data that extends the range well beyond the normal data, it affects the usefulness of the mean. For example, 1, 56, 56 57,76, 67, 75, 64, 190 are a set of numbers. 1 and 190 are outliers. The skew the numbers. 1 Name: __________________________________________________________ Calculating the Mean, Median, and Mode (Answer ID # 1037143) Calculate the values to the nearest hundredth. Select the most accurate measure of central tendency and explain why. Use your notes. 1. 13, 137, 124, 55, 143, 111, 141, 174, 53, 38, and 111 median: _________ mean: _________ mode: _________ 2. 150, 19, 156, 19, 48, 142, 41, 142, 41, and 102 Write the median: _________ Write the mean: _________ Write the mode: _________ 3. 178, 77, 86, 85, 16, 45, 164, 26, 107, 49, 136, 161, and 170 Write the median: _________ Write the mean: _________ Write the mode: _________ 4. 108, 90, 16, 2, 2, 3, 25, and 130 Write the median: _________ Write the mean: _________ Write the mode: _________ 5. Students with the following GPAs applied for a job: 3.5, 2.4, 2, 4, 2.4, 2.4, 2.4, 2.4, 3.2, and 2.6 Write the median: _________ Write the mean: _________ Write the mode: _________ 6. Given the following annual mutual fund returns: 23.04 57.01 39.41 39.41 -40.87 13.45 7.58 39.41 43.1 -43.25 51.17 -49.26 14.53 19.21 23.75 -49.26 17.06 10.96 19.77 -42.09 10.96 -48.44 2.3 42.58 12.73 42.58 29.8 8.08 24.97 13.45 Write the median: _________ Write the mean: _________ Write the mode: _________ 7. The following temperatures were recorded: -3, -7, 62, -1, 53, -9, 12, 19, -6, and 45 Write the median: _________ Write the mean: _________ Write the mode: _________ 2 Name: __________________________________________________________ Find the mean, median, mode and range for each set of data. Select the most accurate measure of central tendency and explain why. Use your notes 1. 2. 39 40 41 42 43 44 45 46 47 68 69 70 71 72 73 74 3. 4. 41 42 43 44 45 46 47 48 26 27 28 29 Complete. 1. 2. 2 3 4 5 6 7 8 1 2 3 4 5 6 Mean_____ Median _____ Mode _____ Mean _____ Median _____ Mode _____ What is wrong with this graph? High Temperatures in October a. How can we improve this data? . 3. Stem Leaves 47 4 5 2 8 51 0 3 60 2 5 b. Is there an outlier? If there is, what is the outlier? 72 4 1 0 c. What is the mean median and mode? 3 Name: __________________________________________________________ Complete. 6. Length of Pieces of Rope a. What is the difference between the lengths of the blue rope and the red rope? b. If it takes twenty-one inches of rope to go all the way around the fence post, how many times will the orange rope go around the post? c. What is the mean median and mode? Complete. 7. Color of Cars in a Parking Lot a. How many cars are there in this study? b. What is the mean median and mode? c. Which color has the least amount of cars in the parking lot? Make a vertical bar graph using the data in the table. 10. Points Scored Player Points Points Scored Steven 6 a. What is the mean for points for all Austin 9 players? Isaac 16 Luis 10 Olivia 3 b. What is the median for points scored? Morgan 18 Jacob 13 Natalie 12 c. Are there any outliers? What is the mode? 4 Name: __________________________________________________________ Complete. 11. This stem-and-leaf plot shows that a. Is there an outlier? If so, then what is it? grades that students received on a math quiz. Test Scores Stem Leaves b. What is the median of the high temperatures 38 recorded? 4 5 65 1 c. What is the mode of the data? 74 8 8 4 8 4 86 2 8 0 95 4 8 6 6 3 1 7 10 0 Complete. 12. Money Spent on Sneakers a. What is the mode? Is there an outlier? b. What is the average amount spent on all 6 sneakers? Round your answer to the nearest cent. c. What is the median of the data? Complete. 14. What Students a. What number of 1000 students drank Drank for Breakfast A Milk 50% orange juice for breakfast? B Water 25% Orange Juice C 16% b. What is the most popular drink? D Soda 9% 5 Name: __________________________________________________________ What sort 4. Using the scatter plot and the trend of trend is line, find the gravity to the nearest shown in tenth, when the altitude is 125 km. the scatter Describe the scatter plot. plot? A wholesale dealer of stationery products plots the scatter diagram of his income through the years 1985 to 2000. Is the data linear? What is your prediction for 2005? 5. Using the scatter plot and the line of 3. The scatterplot shows the details of fit, describe the scatterplot. Predict the a survey on population of 10 cities and number of hours a student needs to the number of educational institutes in study to get a score of 92. these cities. 6 Name: __________________________________________________________ 6. Describe each graph below. Does the line of fit agree with the graph? 9. Describe this scatter plot. What is your prediction for 2002? 10. Create a table that shows the weight of each child as he ages. State which of these graphs are linear, which 7. Describe each graph. Does the line is curved. fit as the correlation for the data points given. 8. The scatter plot displays Sam's weight as he ages. What can you conclude from this data? 7

DOCUMENT INFO

Shared By:

Categories:

Tags:

Stats:

views: | 26 |

posted: | 12/8/2011 |

language: | English |

pages: | 7 |

OTHER DOCS BY gegeshandong

How are you planning on using Docstoc?
BUSINESS
PERSONAL

By registering with docstoc.com you agree to our
privacy policy and
terms of service, and to receive content and offer notifications.

Docstoc is the premier online destination to start and grow small businesses. It hosts the best quality and widest selection of professional documents (over 20 million) and resources including expert videos, articles and productivity tools to make every small business better.

Search or Browse for any specific document or resource you need for your business. Or explore our curated resources for Starting a Business, Growing a Business or for Professional Development.

Feel free to Contact Us with any questions you might have.