# Activities

• • • ##### Subject Area

• Math: Statistics: Inferential Statistics
• Math: Statistics: Probability and Random Variables

• ##### Author 6-8

60 Minutes

• ##### Device
• TI-73 Explorer™
• ##### Other Materials
This is Activity 9 from the EXPLORATIONS Book:
Activities for Algebra with the TI-73.

## You're Probably Right, It's Wrong

#### Activity Overview

In this activity, students perform a simulation to guess answers on a test and determine the experimental probability of passing the test. They then compare it with the theoretical probability.

#### Before the Activity

• Set up the calculator as explained in the attached PDF file
• See the attached PDF file for detailed instructions for this activity
• Print pages 111 - 128 from the attached PDF file for your class
• #### During the Activity

Distribute the pages to the class.

Part 1:

• List the correct answer for each multiple choice question
• Generate a list of random numbers between 1 and 4
• Compare the two lists
• Find the number of correct answers in the simulation
• Use this data to plot a histogram, and find the mean, mode, and median for the number of correct answers
• Compare the experimental and theoretical probabilities for the data

• Part 2:
Run a simulation to check to see if the calculator produces an answer distribution similar to that on the actual test:
• Generate a list of random numbers between 1 and 4 to represent the answers to 20 questions on the test
• Sort the list and count the frequency of each option
• Repeat the steps for two more trials
• Determine the number of times an answer-option occurs in each trial
• Plot a pie chart for each of the trial-tests
• Create a pictograph using the data from the three trials
• Construct bar graphs and observe that this graph shows the results of all three tests
• #### After the Activity

Students will complete the Data Collection and Analysis page and answer questions.

Review student results:

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