Whole Numbers

What is the smallest 2 digit prime?

• 13

• 17

• 11

• 7

What is the smallest prime?

• 3

• 4

• 6

• 2

What are twin-primes?

• 5 composites in the middle

• 1 composite number in the middle

• 2 composite numbers in the middle

• 3 composite numbers in the middle

what are co-primes?

• 2 numbers that do not have a common factor except 1

• 2 numbers that do not have a common factor

• 3 numbers that do not have a common factor

• 3 numbers that do not have a common factor except 1

Which one is divisible by 9?

• 8118

• 190

• 2990

• 2220

what is the divisibility rule for 4

• Last two numbers divisible by 4

• Last 3 numbers divisible by 4

• Add all of the digits and divide by 4

• Even number

Which number is divisible by 6

• 1782

• 1213

• 536

Which number is divisible by 9

• 345

• 8522

• 98874

Why does the divisibility rule for 6, that if a number is divisible by 2 and 3 then it is divisible by 6.

• Because 2x3= 6

• 2 and 3 are the prime factors for 6

• You add up all of the digits and then divide by 6.

Which number is divisible by 4 and 8

• 6657

• 7990

• 554672