Prime Numbers and Their Identification

The video tutorial from Moomoomath explains how to find all prime numbers between 1 and 100. It begins by defining prime and composite numbers, highlighting that 2 is the only even prime number. The method involves circling prime numbers and crossing out their multiples. The process is demonstrated for numbers 2, 3, 5, and 7. The tutorial concludes by identifying the remaining numbers as prime, marked in green.

What is a prime number?

• A number with more than two factors

• A number that is even

• A number with exactly two factors

• A number with only one factor

Tags

CCSS.4.OA.B.4

Why is the number 1 considered a special case?

• It is the largest composite number

• It is both prime and composite

• It is neither prime nor composite

• It is the smallest prime number

Tags

CCSS.4.OA.B.4

What is the only even prime number?

• 4

• 2

• 1

• 0

Tags

CCSS.4.OA.B.4

What is the first step in identifying prime numbers using the given technique?

• Circle all even numbers

• Put a box around number 1

• Cross out all multiples of 2

• Circle all odd numbers

After crossing out multiples of 2, what is the next step?

• Cross out multiples of 3

• Circle all remaining numbers

• Put a box around number 3

• Cross out multiples of 4

Tags

CCSS.4.OA.B.4

Which of the following numbers is a multiple of 3?

• 10

• 15

• 22

• 28

What should be done after crossing out multiples of 3?

• Cross out multiples of 5

• Put a box around number 5

• Circle all numbers ending in 5

• Cross out multiples of 6

Tags

CCSS.4.OA.B.4

Which number is a multiple of 5?

• 47

• 35

• 23

• 12

Tags

CCSS.4.OA.B.4

What is the final step in identifying prime numbers between 1 and 100?

• Put a box around number 7

• Cross out multiples of 9

• Circle all numbers ending in 7

• Cross out multiples of 7

Tags

CCSS.4.OA.B.4

Which of the following numbers is a prime number?

• 53

• 49

• 55

• 51

Tags

CCSS.4.OA.B.4