Education Technology

Picturing Probabilities of Number Cube Sums

Published on 06/09/2008

Activity Overview

Students use ideas of ratio and proportion to investigate various ways to make a circle graph. Students create graphs to display the probabilities of the different sums that can be generated with two number cubes.

Before the Activity

  • See the attached PDF file for detailed instructions for this activity
  • Print student activity sheet page 127 from the attached PDF for your class.

  • During the Activity

    Distribute the page to the class.

    Follow the activity procedures:

  • Record all the ways of rolling two number cubes to get each possible sum of 2 through 12
  • Represent the 11 different sums (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12) with different colors of linking cubes
  • Join all the linking cubes, keeping the same colors together, into a long bar
  • Join the ends of the bar into a circle and place the circle on a large sheet of paper
  • Sketch a circle around the inside of the linking cubes, estimate the center of the circle, and mark sections of the circle by drawing lines from the center to the circumference to show the number of cubes of each color
  • Review with students the angle measure of a circle (360 degrees), and have them work together in small groups to predict the angle measures for each section in the circle graph
  • Use protractors to measure the angles, evaluate the predictions and sketch the results on the recording sheet
  • Use ideas of ratio and proportion to investigate various ways to make a circle graph
  • After the Activity

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