# Worksheet: Prime and Composite Numbers

Q1:

What is a composite number?

• A a number that has one factor repeated
• B a number with exactly two factors, 1 and itself
• C a number with exactly two factors, 0 and itself
• D a number with more than two factors
• Ea number with exactly two factors, 0 and 1

Q2:

What is the greatest prime number between 15 and 24?

Q3:

Caribou calves weigh about 13 pounds at birth. Is the number 13 a prime or a composite number?

• Aprime
• Bcomposite

Q4:

The table shows all the factors of some numbers.

 Number Factor of ( ( π₯ π₯ ) ) 101 133 157 145 1, 101 1, 7, 19, 133 1, 157 1, 5, 29, 145

Which of the numbers are prime?

• A 101 and 133
• B 133 and 145
• C 157 and 145
• D 101 and 157
• E133 and 157

Q5:

Is 23 a prime or a composite number?

• A a prime number
• B a composite number

Q6:

Which of the following is a prime number?

• A 4
• B 8
• C 45
• D 43

Q7:

Madison says that every even number is composite because 2 is a factor.

Is she correct? Why?

• A Yes, because all odd numbers are prime.
• B Yes, because 2 is an even number.
• C Yes, because 2 is even and composite.
• D No, because 2 is even and prime.
• E No, because 2 is even and composite.

Q8:

Is 96 a prime number?

• Ano
• Byes

Q9:

Isabella bought these four raffle tickets, and one of them was the winning ticket.

The winning number is a prime number between 10 and 20. Which of her tickets won the prize?

• A ticket number 34
• B ticket number 15
• C ticket number 23
• D ticket number 17
• Eticket number 18

Q10:

Is 21 a prime or a composite number?

• A a composite number
• B a prime number

Q11:

Find a prime number between 37 and 46.

Q12:

Look at these numbers.

How many of these numbers are prime?

Which is the largest prime number?

Which is the smallest composite number?

Q13:

State two prime numbers that are greater than 15 and less than 95.

• A45, 61
• B44, 60
• C42, 58
• D43, 59

Q14:

Determine whether the number 226 is prime, composite, or neither.

• Aneither prime nor composite
• Bprime
• Ccomposite

Q15:

Are the numbers 37, 97, and 75 prime numbers?

• Ano
• Byes

Q16:

Michael is learning about prime numbers. He knows that 5 is a prime number, because the only factors of 5 are 1 and 5.

Is 9 a prime number? Why?

• A No, because 3 is a factor.
• B Yes, because its only factors are 1 and 9.

Q17:

All odd numbers greater than 7 can be expressed as the sum of three prime numbers. Which three prime numbers have a sum of 97?

• A17, 18, 62
• B16, 20, 61
• C18, 19, 60
• D17, 19, 61

Q18:

Which of the following is not a prime number?

• A2
• B23
• C73
• D68

Q19:

A teacher asked her class to color all the prime numbers between 1 and 10. Here are some of their answers. Which one is correct?

• A
• B
• C
• D
• E

Q20:

All prime numbers are odd except .

Q21:

Find the smallest prime number that is greater than 40.

Q22:

Benjamin says that 1 is a prime number because it only has 1 factor pair.

Is he correct? Why?

• A No, because all odd numbers are prime.
• B Yes, 1 only has one factor.
• C Yes, because all odd numbers are prime.
• D No, prime numbers have two factors, 1 only has one factor.
• ENo, prime numbers have more than two factors, 1 only has one factor.