Prime and Composite

• Factors:–When 2 or more numbers are multiplied,

each number is called a factor of the product

Ex) 1 x 5 = 5 2 x 5 = 10 1 x 10 = 10

** There are special types of numbers**

Neither prime nor composite: 0 and 1

Prime Numbers

• A whole number that has exactly 2 factors, 1 and itself.

Ex) 2, 3, 5, 7, 11……

Composite Numbers

• A number greater than 1 with more than 2 factors.

Ex) 6 10 18

Tell whether each number is prime, composite or neither.

1. 28 2. 37 3. 81

4. 0 5. 19 6. 63

Prime factorization:- Every composite number can be expressed as a

product of prime numbers.

36 29 81

Use: FACTOR TREES