Name:    5th Grade Math- Apply the number theory concepts of primes, composites, and multiples practice test

Multiple Choice
Identify the choice that best completes the statement or answers the question.

1.

If a number can only be divided by 1 and itself, it is known as:
 a. prime number c. multiple number b. composite number d. factor number

2.

If a number has only the factors of 1 and 19, we can say it is what kind of number?
 a. multiple number c. prime number b. composite number d. factor number

3.

Why is 23 a prime number?
 a. It is a double-digit number c. It ends in three b. It can only be divided itself and 1 d. It has more than two factors

4.

7 is a prime number.  Why isn’t 27 a prime number?
 a. It is a double-digit number c. It ends in 7 b. It is prime d. It has factors of 3 and 9 as well

5.

A number has the factors of 1, 3 ,4, 24 and 6.  Why isn’t it a prime number?
 a. It is a double-digit number c. It has more than two factors. b. It has an odd number of factors d. One of its factors is 3.

6.

Which of these numbers is prime?
 a. 79 c. 74 b. 33 d. 93

7.

Which of these numbers is NOT prime?
 a. 37 c. 49 b. 83 d. 53

8.

Why is 9 a composite number?
 a. It has more than 2 factors c. 3 is one of its factors b. It is a one digit number d. Because it is a prime number

9.

Which one of these numbers is a composite number?
 a. 41 c. 81 b. 87 d. 17

10.

Which one of these numbers is NOT a composite number?
 a. 87 c. 81 b. 41 d. 99

11.

If a number includes the factors of 3 and 7, is it composite?  Why?
 a. Yes because the total of 3 and 7 is 10, an even number c. No because 3 and 7 are odd numbers b. No because composite numbers refer to double-digit prime numbers. d. Yes because 3 and 7 factor into many numbers such as 21 and 28.

12.

What do we call a number that can be multiplied by itself and another number to get a third number?
 a. composite c. fraction b. factor d. symmetrical

13.

12 ÷ 3 = 4,   3 x 4 = 12,  12 x 1 = 12,   2 x 6 = 12,   12 ÷ 6 = 2.  What do we call the numbers 3, 4, 2, 6, and 1 in these equations?
 a. composite c. factor b. fraction d. metric

14.

15 ÷ 3 = 5       3 x 5 = 15.  Which number in these equations is a factor?
 a. 3 c. 15 b. 8 d. none

15.

6, 9, 12, 15. These numbers are multiples of which number below?.
 a. 30 c. 18 b. 7 d. 3

16.

Which list below are multiples of 7?
 a. 7, 14, 21, 28, 35, 42 c. 7, 8, 9, 10, 11, 12 b. 7, 15 22, 29, 36, 43 d. 7, 0, 14, 0 21, 0, 28

17.

Which number below is a multiples of 81?
 a. 4 c. 6 b. 9 d. 40