Factors, Prime and Composite Numbers

What is a factor?

• "Factors" are the numbers you multiply to get another number. For instance, factors of 15 are 3 and 5, because 3×5 = 15

• A factor is a number written in word form

• "Factors" tell you facts about all the numbers in the world

Tags

CCSS.4.OA.B.4

Which number is a factor of 10?

• 3

• 5

• 4

• 8

Tags

CCSS.4.OA.B.4

Which number is NOT a factor of 10?

• 1
• 2
• 3
• 5

Tags

CCSS.4.OA.B.4

Is 3 a factor of 12?

• yes
• no

Tags

CCSS.4.OA.B.4

Is 6 a factor of 24?

• Yes

• No

Tags

CCSS.4.OA.B.4

Prime numbers have:

• Exactly 2 factors
• 2 pairs of factors
• More than 2 factors
• 1 factor

Tags

CCSS.4.OA.B.4

Composite numbers:

• Are always bigger than prime numbers
• Have more than 2 factors
• Have 2 pairs of factors
• Don't have factors

Tags

CCSS.4.OA.B.4

Which of these numbers is a prime number?

• 15

• 17

• 21

• 39

Which list is only composite numbers?

• 1, 3, 4

• 3, 4, 6

• 4, 6, 8

• 5, 6, 8

Tags

CCSS.4.OA.B.4

Four students each made a list of prime numbers.
Eric:   5, 7 17, 23
Maya:  3, 5, 13, 17
Bella:  2, 3, 17, 19
Joan:  7, 11, 13, 21
Who made an error and included a composite number?

• Eric
• Maya
• Bella
• Joan

Tags

CCSS.4.OA.B.4