What are Prime Numbers?

The video tutorial explains what prime numbers are, defining them as whole numbers greater than one with exactly two factors: one and itself. It reviews the concepts of whole numbers and factors, providing examples to clarify these terms. The tutorial introduces a strategy to identify prime numbers by asking two key questions and demonstrates this with examples. It also discusses non-prime numbers, explaining why certain numbers do not qualify as prime. The video concludes with practice exercises and a vocabulary review to reinforce the concepts covered.

What is a prime number?

• A number with a decimal

• A number that is divisible by 2

• A whole number greater than one with exactly two factors

• A number with more than two factors

Which of the following is a prime number?

• 4

• 8

• 6

• 5

Why is the number 2 considered a special prime number?

• It is not a whole number

• It has more than two factors

• It is the largest prime number

• It is the only even prime number

Which of the following numbers is NOT a prime number?

• 11

• 9

• 7

• 13

What is the sum of the digits of 57, and why is it relevant?

• 15; it shows 57 is divisible by 5

• 10; it shows 57 is a prime number

• 12; it shows 57 is divisible by 3

• 9; it shows 57 is a whole number

Which of the following statements is true about whole numbers?

• They can have decimals

• They are always prime numbers

• They can have fractions

• They are written without fractions or decimals

What are factors?

• Numbers that are subtracted

• Numbers that are divided

• Numbers that are added together

• Numbers that are multiplied