MathsNet: Illuminations Tools

The Factor Game

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Factor Game Rules

The Factor Game Board
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Player A chooses a number on the game board by clicking on it with the mouse. This colors the number.
Using a different color, Player B clicks on all the proper factors of Player A's number. The proper factors of a number are all the factors of that number, except the number itself. For example, the proper factors of 12 are 1, 2, 3, 4, and 6. Although 12 is a factor of itself, it is not a proper factor.
Player B colors a new number, and Player A colors all the factors of the number that are not already colored.
The players take turns choosing numbers and coloring factors.
If a player chooses a number that has no factors left that have not been colored, that player loses a turn and does not get the points for the number colored.
The game ends when there are no numbers remaining with uncolored factors.
Each player adds the numbers that are colored with his or her color. The player with the greater total is the winner.

This applet is produced by Illuminations, a partnership between the National Council of Teachers of Mathematics, NCTM, and the MarcoPolo Education Foundation, MarcoPolo Education Foundation

The mission of the National Council of Teachers of Mathematics is to provide the vision and leadership necessary to ensure a mathematics education of the highest quality for all students. The NCTM Illuminations Web site is devoted to providing Internet resources to improve the teaching and learning of mathematics in grades pre-K through 12. The views expressed or implied on this Web site, unless otherwise noted, should not be interpreted as official positions of the Council.