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

Prime numbers have:

• Exactly 2 factors

• 2 pairs of factors

• More than 2 factors

• 1 factor

is 5 prime or composite?

• prime

• composite

Which number is a factor of 10?

• 3

• 5

• 4

• 8

The number 11 is​ (a)   because it has ​ (b)  

• prime

• composite

• exactly 2 factors

• more than 2 factors

Are each of these numbers prime or composite?

• prime

• 15

• composite

• 7

• composite

• 12

• composite

• 10

• prime

• 3

The number 21 is ​ (a)   because it has ​ (b)  

• composite

• prime

• more than 1 factor pair

• exactly 1 factor pair

The number 17 is ​ (a)   because it has ​ (b)  

• prime

• composite

• exactly 1 factor pair

• more than 1 factor pair

The number 25 is ​ (a)   because it has ​ (b)  

• composite

• prime

• more than 2 factors

• exactly 2 factors

1 is neither prime nor composite

• True

• False