Prime Time Factors and Products

1. Prime TimeFactors and Products 1.1 Playing the Factor Game

2. Vocabulary • Factor: One of 2 or more whole numbers that are multiplied to get a product. • For Example, 13 and 4 are both factors of 52 because 13 x 4 = 52 • Divisor: A number that divides is a given number leaving a zero remainder. • For Example, 5 is a divisor of 20 since 20 ÷ 5 = 4 and has a remainder of 0. A divisor is also known as a factor of that number. Another way to determine if 5 is a divisor of 20 is to ask whether there is a whole number that when multiplied by 5, gives 20. The number is 4. 5 x 4 = 20.

3. The Factor Game Board 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30

4. Factor Game Rules • Player A chooses a number on the game board and circles it. • Using a different color, Player B circles 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 circles a new number, and Player A circles all the factors of the number that are not already circled. • The players take turns choosing numbers and circling factors. • If a player circles a number that has no factors left that have not been circled, then that player does not get the points for the number circled and loses the next turn. • The game ends when there are no numbers left with uncircled factors. • Each player adds the numbers that are circled with his or her color. The player with the greater total is the winner.

5. Example Game CathySara 24 36

6. Example Game CathySara 24 36 21 28

7. Example Game CathySara 24 36 21 28 27 9

8. Example Game CathySara 24 36 21 28 27 9 30 30

9. Example Game CathySara 24 36 21 28 27 9 30 30 0 0 No points received!

10. Practice, Practice, Practice!