1. MJ2 Ch 2.7 – Bar Graphs & Histograms

2. Bellwork Please take out your homework from yesterday and leave it on your desk for me to check Analyze the pie chart. Identify the error(s) Student Favorite Ice Cream Flavor Number of Students Surveyed Vanilla52 Chocolate37 Strawberry23 Vanilla Chocolate Strawberry 52%37% 23 %

3. Assignment Review Text p. 420 # 5 & 6; p. 421 # 12-14

4. Before we begin… Please take out your notebook and get ready to work… Today we will discuss bar charts and histograms which, are two more tools that can help you organize and interpret data… It is expected that you already know how to construct these types of charts…so this should be a quick review

5. Objective Students will construct and interpret bar charts and histograms

6. Comparison Raise your hand if you already know the difference between a bar chart and a histogram…

7. Difference A bar chart is a method of comparing data by using bars to represent quantities A histogram is a special type of bar chart. The histogram uses bars to represent frequencies of numerical data that have been organized in intervals Essentially, in a bar chart each of the bars is separated by a space. In a histogram the bars are connected and represent ranges of numbers

8. Constructing a Bar Chart To construct a bar chart Draw a horizontal & vertical axis. Label the axes. Depending upon how you label the axes the bars will be horizontal or vertical Add a title – Note: All charts are required to have a title identifying what the data represents. Lets see what that looks like…

9. Example Using the data from the table construct a bar chart Demonstrate on Board AnimalSpeed Cheetah70 Wildebeest50 Lion50 Elk45 Zebra40

10. Interpreting the Data The bar chart provides a quick visual of the data… From the bar chart we can Identify which animal is fastest… Identify animals that run at the same maximum speed… Identify the slowest animal of the groups represented…

11. Constructing a Histogram To construct a Histogram Draw a horizontal & vertical axis. Label the axes. Depending upon how you label the axes the bars will be horizontal or vertical Draw a bar to represent the frequency of each interval – Note: There should be no space between the bars Add a title – Note: All charts are required to have a title identifying what the data represents. Lets see what that looks like…

12. Example The number of wins for the 29 teams of the NBA have been organized into a frequency table Construct a Histogram Demonstrate on Board Number of Wins Frequency 11 – 203 21 – 304 31 – 404 41 – 5010 51 – 608

13. Interpreting the Data The histogram provides a visual of the data… From the histogram we can Identify the range of the highest winners See that most teams had between 41 – 60 wins Identify least number of wins However, we can not identify the individual team with the most wins…

14. Summary In the notes section of your notebook summarize the key concepts covered in today’s lesson Today we discussed Bar Charts & Histograms What is the difference between the two?

15. Classwork Ch 2 Resource Book p. 99 Lesson 2.7 Word problems… This is an individual assignment that is due at the end of class… Read the directions before you begin…

16. Assignment Workbook – Lesson 2.7 Pg. ____# 1 – 6