Warm Up Problem of the Day Lesson Presentation Lesson Quizzes

Warm Up Solve. 1. 6n – 10 = 44 2. 27 = 3 – 8n 3. 41 + 7x = –8 n = 9

Problem of the Day A data set has a range of 24 and a mean of 104. If the data set contains three numbers and the highest number is 118, then what are the other two numbers in the data set? 94 and 100

Learn to select the best representation for a set of data.

Data can be represented in several different ways, depending both on the type of data and the message to be conveyed.

Additional Example 1A: Selecting a Data Display Which graph is a better display of the data on temperature changes? 40 50 60 70 80 The line graph shows the change in data over time, so it is the better representation.

Additional Example 1B: Selecting a Data Display Which graph better shows the relationship between the two data sets? xx x x x x x 1 2 3 4 5 6 7 8 9 10 11 12 The scatter plot shows the relationship of two sets of data, so it is the better representation.

Check It Out: Example 1A Which graph is a better display of the number of students who own a dog, versus a snake? The bar graph shows a relationship or comparison between groups, so it is the better representation.

Check It Out: Example 1B Which graph is a better display of Macarena’s height? The line graph shows the change in data over time, so it is the better representation.

Additional Example 2: Problem Solving Application Groceries $400 Utilities $350 Mortgage $850 Clothing $200 Entertainment $100 Auto $500 Savings Misc. $120 The Singer family keeps the budget shown below for their monthly expenses. Choose an appropriate data display and draw the graph. Which two categories account for one-fifth of their budget?

Understand the Problem Additional Example 2 Continued 1 Understand the Problem You are looking for the best data display and the two categories that take up one-fifth of the Singer family budget . 2 Make a Plan You need to find one-fifth of the whole amount of the budget. Since the data can be organized as a whole, display it in a circle graph.

Additional Example 2 Continued Solve 3 Create a circle graph. For each category calculate the percentage spent. The 2 categories that add up to one-fifth or 20% of the Singer’s budget are auto and entertainment.

Additional Example 2 Continued 4 Look Back Look at the table. Entertainment has a budget of $100 and Auto has a budget of $500. So, $600 of the total budget of $3,020, is approximately 20%. The answer is reasonable.

Check It Out: Example 2 The table shows the number of new students every two years from 1990 to 2004. Choose an appropriate data display and draw the graph. About how many new students were there in 2003? 1990 4 1992 8 1994 14 1996 16 1998 22 2000 30 2002 42 2004 50

Understand the Problem Check It Out: Example 2 Continued 1 Understand the Problem You are looking for the best data display and the number of new students in 2003. 2 Make a Plan You need to find an estimate of the number of new students in 2003. Since the data occurs over time you can use a line graph.

Check It Out: Example 2 Continued Solve 3 Create a line graph. For each year plot a point and connect the line. You can estimate that in 2003 there were about 48 new students.

Check It Out: Example 2 Continued 4 Look Back Look at the table. In 2002 there were 42 new students. In 2004 there were 50 new students, so the answer of 48 new students in 2003 in reasonable.

Lesson Quiz for Student Response Systems Lesson Quizzes Standard Lesson Quiz Lesson Quiz for Student Response Systems 18

Lesson Quiz: Part I 1. Which is a better display of the number of miles ran by members of the track team during one week: a box-and-whisker plot or a scatter plot? box-and-whisker plot

Lesson Quiz: Part II 2. The number of boys and girls enrolled in a middle school is shown in the table. Choose an appropriate display for this data and draw the graph. What percent of the students at the middle school are boys? Grade Girls Boys 6 140 117 7 133 145 8 130 115

Lesson Quiz: Part II Continued  48.3%

Lesson Quiz for Student Response Systems 1. Which of the following is a better display of a class’s test scores? A. scatter plot B. histogram C. circle graph D. box-and-whisker plot 22

Lesson Quiz for Student Response Systems 2. The diameters of four planets are shown in the table. Identify an appropriate display for this data and the graph that represents the data. Identify the planet that has the second largest diameter. A. Venus B. Venus 23