The Probability Simulation application on the TI-84 Plus can simulate spinning a spinner that is divided into two to eight sections of equal or unequal areas. It will not simulate the spinner landing on the boundary of two sections. An outcome of this simulator is the section on which the spinner landed.

The data from the repeatedly spinning the spinner can be displayed in a histogram or in a table. The application even gives you the option of saving your data so you can, if you choose, statistically analyze it at a later time.

## How to spin spinners in Probability Simulation

To spin a spinner, follow these steps:

1. Start the Probability Simulation application and press [4] to select the Spin Spinners option in the Main menu.

You see the Spin Spinner simulator’s Home screen.

To use the Spin Spinner simulator after using another simulator, repeatedly press [Y=] until you see the Main menu, and then press [4] to select the Spin Spinners simulator.

2. Press [ZOOM] to display the Settings editor. Change the settings in Settings editor as appropriate.

You see a screen similar to the Toss Coins simulator’s Settings editor.

The Sections option lets you tell the application how many sections you want the spinner to have. It can have from two to eight sections.

To enter a number in Trial Set or Sections, use the arrow keys to place the cursor on the existing number, use the keypad to enter a new positive integer, and then press [ENTER]. To select other options, use the arrow keys to place the cursor on the option and press [ENTER] to select the option.

3. Press [WINDOW] to display the Advanced Settings editor. Enter the weight of each section of the spinner.

The number of the section is displayed in the first column of the Advanced Settings editor, its weight appears in the second column, and the probability of the spinner landing on that section appears in the third column. The weight corresponds to the area of the spinner occupied by that section.

For example, if you want a spinner to have three sections with one section occupying half the area of the spinner and the other two sections each occupying a fourth of the spinner, set the weight of one section to two and the weight of the other two sections to one.

To change a number in the weight column, use the arrow keys to place the cursor on the existing number, use the keypad to enter a new positive integer, and then press [ENTER].

4. Press [GRAPH] to say OK to the weights in the Advanced Settings editor. Press [GRAPH] again to say OK to the settings in the Settings editor.

You see the Spin Spinner Home screen.

5. Press [WINDOW] to spin the spinner.

You see a screen similar to the second picture. The number on which the spinner last landed appears at the top of the screen.

6. Continue spinning the spinner.

If in Step 2 you set Trial Set to a number greater than one, press [WINDOW] to spin the spinner the number of times specified in Trial Set.

If Trial Set is 1, then after the first spin of the spinner the command line at the bottom of the screen is the same as the command line in the second picture. Press [WINDOW] to spin the spinner one time, [ZOOM] to spin the spinner ten more time, or [TRACE] to spin it 50 more times.

## How to read the Spin Spinner graph and table

The cumulative data from spinning the spinner is stored in both a histogram and a table. The histogram, by default, is displayed on the screen without any values on the y-axis. Here are some specifics about the Spin Spinner simulator’s histogram and table:

• Spin Spinner histogram: Each bar in the histogram records the data for each section of the spinner.

• Spin Spinners table: The first column displays the number of the spin and the second column shows where the spinner landed.