Lesson 12.3 Appropriate Data Displays Essential Question: How do you make a circle graph and line graph? Which data display do you select to use?

Before we start… What data display(s) shows a change in data over time? What data display(s) shows data in distinct categories? What data display(s) always places data in increasing order?

What is a circle graph? Represents data as parts of a circle Each item is one part Adds up to 1 or 100%

How do you make a circle graph? Find the angle measure for each section. 𝑝% 100 = 𝑎 360° Draw a circle. Draw the sections of the circle using the angle. Write a title for the graph.

Siblings The table shows the results of a survey that asked students how many siblings they have. Make a circle graph. Siblings Percent None 10% One 40% Two 25% Three or More

Email A survey asked, “How often do you check your email Email A survey asked, “How often do you check your email?” Of the 100 people asked, the results are displayed in the table. Make a circle graph of the data. Frequency People Less than weekly 4 Weekly 23 Every day 73

Clothing The table shows the results of a survey that asked students what they wear to school. Make a circle graph. Clothing Percent Jeans 55% Skirts 15% Dress Pants 30%

What is a line graph? A type of graph in which points representing data pairs are connected by line segments. Line graphs show a change in data over time.

How do you make a line graph? Choose horizontal and vertical axes. Draw and label the graph. Plot a point for each year. Connect the points with line segments. Include evenly spaced gridlines.

Cell Phones Use the table to make a line graph of the number of cellular phone subscribers from 1998 through 2003. What can you conclude? Year 1998 1999 2000 2001 2002 2003 Subscribers (millions) 69 86 109 128 141 159

Environment The table shows the number of insect species on the United States endangered species list. Make a line graph of the data. Year 1994 1996 1998 2000 2002 2004 Number of Insects 19 20 28 33 35

How do you choose an appropriate display for the data? The type of data given determines the graph used. A circle graph to display data as parts of a whole A bar graph to display data in distinct categories A line graph to display data over time A stem-and-leaf plot to group data into ordered lists A box-and-whisker plot to display how the data are spread out A Venn diagram to display data in overlapping categories A histogram to compare the frequencies of data that fall in equal intervals

The table shows the total United States population over several years The table shows the total United States population over several years. What type of data display would best represent the data?

The table shows the results of a survey that asked students if they are going away during summer vacation. What type of display would you use?

The table shows the results of a survey that asked students why they use the Internet. What type of display would you use?

You are given a list of numbers in no particular order You are given a list of numbers in no particular order. What data display would you use to organize the data in numerical order?

A bookstore sells eight different types of books A bookstore sells eight different types of books. Which data display(s) should be used to compare the number of each type of book in stock?

Bowling A professional bowler wants to display his scores for the year, without displaying individual data. What data display(s) should he use?

Misleading Data Display You need to be able to identify potentially misleading data displays so that you interpret them correctly.

Is the graph potentially misleading? Explain.

How do you choose an appropriate display for a data set?

Ticket Out the Door What display would you use to determine how spread out data are?