Factors, Multiples, Divisibility Rules, Prime Factorization

A composite number is:

• All even numbers
• All odd numbers
• All negative numbers
• All numbers that are not prime, except 0 and 1 which are neither prime nor composite.

Which number is divisible by 2, 3, and 5?

• 45
• 66
• 77
• 90

Which number is divisible by 9?

• 10,233
• 15,941
• 24,207
• 39,671

Celia has 2,880 beads and wants to place the same number of beads in each of 9 clear storage containers. Which of the following will help determine if 2,880 is divisible by 9?

• 2,880 is an even number and divisible by 3, so 2,880 is divisible by 9.
  
• 288 is an even number, so 2,880 is not divisible by 9.
  
• 2 + 8 + 8 + 0 = 18 and 18 is divisible by 9, so 2,880 is divisible by 9
• 8 + 0 = 8 and 8 is not divisible by 9, so 2,880 is not divisible by 9.
  

Which of the following has factors of 1, 2, 7, and 14?

• 7
• 14
• 21
• 27

What are all the factors of 20?

• 1, 20
  
• 1, 2, 10, 20
• 1, 2, 5, 10, 20
  
• 1, 2, 4, 5, 10, 20
  

Which number is divisible by 2, 3, 5, and 7?

• 20
• 42
• 70
• 210

What is the missing digit or digits that would make this number divisible by 5?
24,45__

• Zero
• Only 5 
• Either zero or 5
• Zero, 2, or 5

Which number is divisible by 2, 3, 4, 5, and 9?

• 360
• 120
• 190
• 210

Which number is not prime? 

• 13
• 11
• 23
• 27