# Activities

• • • ##### Subject Area

• Math: Algebra I: Exponential Functions
• Math: Statistics: Inferential Statistics

• ##### Author 9-12

60 Minutes

• ##### Device
• TI-83 Plus Family
• TI-84 Plus
• TI-84 Plus Silver Edition

TI Connect™

• ##### Accessories

TI Connectivity Cable

• ##### Other Materials
This is Activity 3 from the EXPLORATIONS Book:
EasyData Activities: Modeling Algebraic Functions with Data Collection Activities.

#### Activity Overview

Students examine patterns and use these patterns to try to predict different aspects of an event. They study the statistical patterns for the population of the state of Nevada over a period of hundred years, and predict the population in the year 2010. Students learn to graph scatter plots, graph and analyze exponential functions, and interpret, estimate, and predict data.

#### Before the Activity

• See the attached PDF file for detailed instructions for this activity
• Print pages 15 - 22 from the attached PDF file for the class
• Set up the calculator for data collection
• #### During the Activity

Distribute the pages to the class.

• Enter the data for the year and the corresponding population as lists
• Create a scatter plot
• Understand that the population is graphed as a function of the year
• Realize that the shape of the plot is exponential, and resembles 'half a parabola'
• Identify and predict an equation type that would generate the shape displayed on the graph
• Perform an exponential regression and find the equation of the best fitting curve
• Determine the correlation coefficient ( r ); and understand that closer the absolute value of 'r' is to 1, the better the equation fits the data
• View the graph of both, the plotted points and the regression equation
• Trace the graph of the equation and understand that the values to the right are the populations for the near future
• Set up a table of these values and use the calculator to estimate the population of the state in the future
• #### After the Activity

• Students analyze the results and answer the case analysis questions on the student worksheet.
• Review student results
• As a class, discuss questions that appeared to be more challenging
• Re-teach concepts as necessary