# Activities

• • • ##### Subject Area

• Math: Algebra I: Linear Functions

• ##### Author 9-12

60 Minutes

• ##### Software

TI InterActive!™

• ##### Other Materials
This Activity is from the EXPLORATIONS Book:
TI InterActive!™ Data Collection and Analysis

• ##### Report an Issue

Two Hot, Two Cold

#### Activity Overview

In this activity, students collect Celsius and Fahrenheit temperature data for various cities across the world. They develop and test a mathematical relationship between the two temperature scales. This is Activity 5 from the EXPLORATIONS book, TI-InterActive!™ Data Collection and Analysis (Texas Instruments Incorporated, 2000).

#### Before the Activity

• Open a new TI InterActive!™document
• See the attached PDF file for detailed instructions for this activity
• Print pages 27 - 32 from the attached PDF file for your class
• #### During the Activity

Distribute the pages to the class.

• From the CNN weather webpage find the high and low temperatures in Celsius and Fahrenheit scales of cities listed and 2 other cities of choice and record the data on the sheet
• Graph Fahrenheit temperatures versus Celsius temperatures, and observe that the graph is linear and increasing
• Find the slope of the line using the coordinates of two points on the line
• Enter the x and y values of a point in the equation y = mx + b and find the y-intercept(b)
• Use basic algebraic techniques to solve for the unknown and find the value of b
• Form a new linear equation which shows relationship between Fahrenheit and Celsius temperature scales and is of the form y = mx + b
• Use the linear regression function to get a line that best fits the data and record the linear equation y = ax + b and values of a and b
• Find the values of 100 and 22 degrees Celsius in Fahrenheit using both the model and regression model equations
• Observe that the values found using both equations are close to the actual values of 212 and 70 degrees Fahrenheit
• #### After the Activity

Students complete the analysis and answer questions.

Review student results:

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