Education Technology

# Activities

• ##### Subject Area

• Math: PreAlgebra: Probability, Statistics and Data Analysis
• Math: Middle Grades Math: Statistics and Probability

6-8

60 Minutes

• ##### Device
• TI-30X IIB
• TI-30X IIS
• TI-34 II Explorer Plus™
• ##### Other Materials
This is Activity 2 from the EXPLORATIONS Book:
Math Investigations with the TI-30X IIS and TI-34 II: Activities for the Middle Grades

The following material may be required for this activity:
• The Phantom Tollbooth by Norman Juster

## Parts is Parts

#### Activity Overview

Students find a sample of a given size with a given mean. Students will show one way 100 families can have a mean of 2.58 children and understand the meaning of the term "average."

#### Before the Activity

• Understand the concept of "average" in mathematics
• Study the calculator keystrokes as explained in the activity
• See the attached PDF file for detailed instructions for this activity
• Print pages 13 - 18 from the attached PDF file for your class
• #### During the Activity

Distribute the pages to the class.

• Prepare a plan to show exactly 100 families that have an average of 2.58 children
• Understand that since the mean is between 2 and 3, some families with 2 children and some families with 3 children should be used for the sample
• Realize that since the mean is closer to 3 than 2, more families with 3 children should be used
• Record the number of families which have 2 children
• Record the number of families which have 3 children
• Make a plan with exactly 100 families
• Calculate the total number of children
• Try to ensure that the total number of children does not exceed 258 [because the mean is 2.58]
• If the number of children exceeds 258, trade in some larger families for some smaller ones
• If the number of children is less than 258, trade in some smaller families for some larger ones
• Create other plans with families having 1, 2, 3, and 4 children
• #### After the Activity

Students complete the Student Activity pages and answer questions.

• Review student results
• As a class, discuss questions that appeared to be more challenging
• Re-teach concepts as necessary