8th Grade Data Analysis and Probability Name: Date: Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (1 of 7 )
1. Plainview High School mailed a survey to the students who graduated the previous year. The survey asked the students whether or not they are enrolled in a college. The results of the students who returned the survey are shown. There are 254 students. 172 of the students are females. 48 of the males enrolled in college. 124 of the females enrolled in college. Complete the two-way table based on the given data. Calculate the relative frequency of all the females surveyed who have enrolled in college and the relative frequency of all the males surveyed who have enrolled in college. Explain your answers. Should the average of the two relative frequencies you found be equal to the relative frequency of all the students surveyed who have enrolled in college? Explain why or why not. 2. The scatter plot shows the relationship between the age of a reader and the time, in hours, the reader spends reading each month. Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (2 of 7 )
What type of association (positive or negative) is shown between the age of the reader and the hours spent reading per month? Explain your answer. Does the data represented show a linear or nonlinear relationship? Explain your answer. Write an equation that would best represent the data shown in the scatter plot. Part D Explain what information the numbers you used in the equation for represents in the scatter plot. 3. The altitude of an airplane taking off from an airport is represented by the equation shown, where y represents the altitude, in feet, of the airplane and x represents the number of minutes since take-off. What is the altitude of the airplane after 5 minutes? 30 minutes? Show your work. Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (3 of 7 )
Create a table for the values when Write your answers from as ordered pairs. Part D Which ordered pair represents the y -intercept? What information does the y -intercept represent? Part E What is the slope of the equation? What information does the slope represent? 4. Jenny wanted to know if people were more likely to beep their horns at a certain time during the day. One night she recorded the number of times she heard a car horn during one hour intervals. What should be the value of the missing y-coordinate so that the data can be modeled with a linear function? A)24 B)25 C)26 D)27 Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (4 of 7 )
5. The scatter plot shows the relationship between the number of tickets sold for a play and the revenue earned from ticket sales for each performance. There are 2 different prices for tickets: one price for adults and a significantly lower price for children. Does this scatter plot have a positive association, a negative association, or no association? Explain your answer. Are there any outliers in the scatter plot? If so, approximate the coordinates of the point of any outliers and explain why the point is considered an outlier in using the information provided in this problem. If you informally fit a straight line to suggest linear association, what would be a likely amount of revenue earned for 150 tickets sold? Explain your reasoning. 6. The two-way table shows data about all the students at Central Junior High School and their enrollment in band, chorus, or neither. Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (5 of 7 )
How many more students in Grade 8 are not enrolled in band or chorus than the number of students in Grade 7 who are not enrolled in band or chorus? Show or explain your work. How many more students in Grade 7 and Grade 8 combined are in band than are in chorus? Show or explain your work. There are 323 students in Grade 7 and 336 students in Grade 8. How many students in each grade are in both band and chorus? Show or explain your work. Part D Using your answer from, copy and complete the Venn diagram for the total number of students in both grades who are in band, chorus, both, or neither. 7. A researcher collected data on monthly rental charges for commercial properties. Using the data points, the researcher estimated that the equation of the line of best fit is where x is the area in square feet of the rented property Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (6 of 7 )
and y is the monthly rent in dollars. Explain how the researcher could have estimated an equation for a line of best fit from the data. What is the slope of the line of best fit? Explain what the slope represents in this situation. One of the commercial properties has a monthly rent of $2,500. Substitute this amount in the line of best fit equation and then solve the equation. Explain exactly what your solution represents. Copyright 2014 by Georgia Department of Education. Items shall not be used in a third party system or displayed publicly. Page: (7 of 7 )