Problem-Solving Application: Using Data from Graphs Lesson 1-13 Pg. # 32-33

CA Content Standards  Statistics, Data Analysis, and Probability 2.3: I can analyze data and explain why the way in which the results are displayed might have influenced the conclusions reached.  Mathematical Reasoning 2.4: I use a variety of methods, such as words, numbers, graphs, and tables to explain mathematical reasoning.

Vocabulary: BAR GRAPH  A convenient tool for organizing statistical data. Provides a quick summary of the data and relationships among data.  Bars are used to show quantities.

Objective  Analyze and interpret data in bar graphs.

Example 1.  Sherrie is training for the LA Marathon, which is approximately 26 miles long. The table below shows a week’s worth of Sherrie’s training days. Sherrie’s Training Sessions Day# of Miles Ran Monday4.5 Tuesday3.25 Wednesday0.75 Thursday6.5 Friday7

Example 2.  Miss Flores surveyed her 6th period class to investigate which is the preferred wireless provider: Sprint, AT&T (Cingular), or Verizon. Results are shown in the table below. Wireless Provider Preference SprintAT&TVerizon 71015

Parts of a Bar Graph TITLE X-Axis Units Y-Axis Units Y-Axis Scale

Scale Does Matter… Scale: 2 Scale: 5

Two Ways to Display… Vertical Bar Graph Horizontal Bar Graph

Double Bar Graph  Say that Miss Flores wants to separate the wireless preference results of her sixth period into girls and boys. Her display would have to look different to incorporate this new information. Take a look at the data table below. Wireless Preference by Gender SprintAT&TVerizon GirlsBoysGirlsBoysGirlsBoys

The Moral of the Story:  You can analyze data in bar graphs by reading and interpreting the unit labels and the scale on the graph.