3. What are Factors?

4. FACTOR Definition #1: A Whole Number that divides evenly into another number

5. FACTORS DIVIDE Evenly into ANOTHER NUMBER What numbers divide into 12 (without a remainder)? 12 ÷ 1 = 12 12 ÷ 2 = 6 12 ÷ 3 = 4 12 ÷ 4 = 3 12 ÷ 6 = 2 12 ÷ 12 = 1 1, 2, 3, 4, 6, and 12 are the FACTORS of 12.

7. FACTOR Definition #2: A Whole Number that multiplies with another number to make a third number

8. MULTIPLY Factors to get ANOTHER NUMBER What numbers, multiplied together, equal 12 ? 1 x 12 = 12 12 x 1 = 12 2 x 6 = 12 6 x 2 = 12 3 x 4 = 12 1, 2, 3, 4, 6, and 12 are the FACTORS of 12.

9. STRATEGY #1 for finding ALL FACTORS Use counters to make all possible arrays: record as factor pairs 2 x 6 = 12 3 x 4 = 12 1 X 12 = 12 FACTORS: 1, 2, 3, 4, 6, 12

10. STRATEGY #2 for finding ALL FACTORS Use MULTIPLICATION Facts Think of two numbers that have a product of 12, or use a times table.

11. STRATEGY #3 for finding ALL FACTORS Divide & Organize work in a data table note: this strategy works, but it’s not always efficient. A Factor of 12? 12÷ 1= 12yes 12÷ 2= 6yes 12÷ 3= 4yes 12÷ 4= 3yes 12÷ 5= 2 r 2no 12÷ 6= 2yes 12÷ 7= 1 r 5no 12÷ 8= 1 r 4no 12÷ 9= 1 r 3no 12÷ 10= 1 r 2no 12÷ 11= 1 r 1no 12÷ 12= 2yes

12. PRACTICE: Find ALL FACTORS of 16 Go on to next slide when you are ready to check your answers.

13. STRATEGY #1 for finding ALL FACTORS Use counters to make all possible arrays: record as factor pairs

14. Use Math Facts (note: 1 x16 & 16 x 1 is not on chart)

15. STRATEGY #2 for finding ALL FACTORS Divide & Organize work in a data table A Factor of 16? 16÷ 1= 16yes 16÷ 2= 8yes 16÷ 3= 5 r 1no 16÷ 4= 4yes 16÷ 5= 3 r 1no 16÷ 6= 2 r 4no 16÷ 7= 2 r 2no 16÷ 8= 2yes 16÷ 9= 1 r 7no 16÷ 10= 1 r 6no 16÷ 11= 1 r 5no 16÷ 16= 1yes