Education Technology

# Activities

• ##### Subject Area

• Math: Geometry: Circles

6-8
9-12

45 Minutes

• ##### Device
• TI-73 Explorer™
• TI-83
• TI-83 Plus Family
• TI-84 Plus
• TI-84 Plus Silver Edition
• ##### Other Materials
You will need snack cakes in three different sizes.

## To The Moon

#### Activity Overview

Students will use linear regression to generate the formula for circumference.

#### Before the Activity

Take your Moon Pie out of the wrapper and measure the distance around the outside edge in cm. Measure the distance across the middle and through the center in cm. The distance around the outside edge is called circumference and the distance through the middle is called diameter. The radius is ½ of the diameter. Write you results below.

#### During the Activity

Repeat with your Mini-moon Pie.
Repeat with your Little Debbie Cake.

Enter the data into your list using the STAT, EDIT commands on the TI 83/84 or the LIST key on the TI 73. Put diameter in list 1, circumference in list 2..

#### After the Activity

Review with students' as necessary.