Understanding Prime and Composite Numbers

The video tutorial introduces prime and composite numbers, explaining their definitions and differences. It uses examples with donuts to illustrate how numbers can be divided. The video further explains factors and divisibility rules, and demonstrates the Sieve of Eratosthenes method to find prime numbers. Viewers are encouraged to practice using provided worksheets.

What is a composite number?

• A number that is only divisible by 2

• A number that can only be divided by 1 and itself

• A number that can be divided by numbers other than 1 and itself

• A number that is neither prime nor composite

How many groups can you divide 6 donuts into, where each group has more than one donut?

• 3 groups of 2

• 2 groups of 3

• 1 group of 6

• Both 2 and 3

Why is the number 7 considered a prime number?

• It can be divided by 1, 2, and 7

• It can be divided by 1, 2, 3, and 7

• It can be divided by 1 and 7 only

• It can be divided by 1, 3, and 7

Which of the following numbers is neither prime nor composite?

• 2

• 1

• 0

• 3

Which of the following numbers is a composite number?

• 2

• 3

• 5

• 4

What are factors?

• Numbers that are always composite

• Numbers that can be divided by 1

• Numbers that can be multiplied to get another number

• Numbers that are always prime

Which number has exactly two factors?

• 8

• 5

• 6

• 4

What is the main characteristic of a prime number?

• It has no factors

• It has only one factor

• It has exactly two factors

• It has more than two factors

What is the quickest way to find factors of larger numbers?

• Guessing

• Using divisibility rules

• Using a calculator

• Using a multiplication table

What is the Sieve of Eratosthenes used for?

• Finding even numbers

• Finding composite numbers

• Finding prime numbers

• Finding odd numbers