Prime and Composite Numbers Worksheet

**Page 3**

21.

_____ is the only even and the smallest prime number.

a. | 1 | ||

b. | 3 | ||

c. | 2 |

Correct answer : (4)

22.

Every _________ number can be written as the product of prime numbers.

a. | Whole | ||

b. | Prime | ||

c. | Composite | ||

d. | None of the above |

Correct answer : (3)

23.

Since 1 has only _____ factor(s), it is neither prime nor composite.

a. | 4 | ||

b. | 2 | ||

c. | 1 |

Correct answer : (4)

24.

The greatest prime number less than 100 is ____ .

a. | 99 | ||

b. | 91 | ||

c. | 97 | ||

d. | 95 |

Correct answer : (3)

25.

Every ________ number greater than 2 is either prime or composite.

a. | Real | ||

b. | Complex | ||

c. | Whole | ||

d. | Natural |

Correct answer : (3)

26.

Which of the following is not a prime number?

a. | 2 | ||

b. | 17 | ||

c. | 11 | ||

d. | 12 |

Factors of 11: 1 and 11

Factors of 19: 1 and 19

Factors of 17: 1 and 17

Factors of 12: 1, 2, 3, 4, 6, 12

The number 12 has more than 2 factors.

So, the number 12 is not a prime number.

Correct answer : (4)

27.

Which of the following is not a composite number?

a. | 12 | ||

b. | 17 | ||

c. | 22 | ||

d. | 26 |

Factors of 26: 1, 2, 13 and 26

Factors of 22: 1, 2, 11 and 22

Factors of 17: 1 and 17

Factors of 12: 1, 2, 3, 4, 6, 12

The number 17 has exactly 2 factors, 1 and 17.

So, the number 17 is not a composite number.

Correct answer : (2)

28.

Which of the following arrays shows a prime number?

a. | Figure 3 | ||

b. | Figure 1 | ||

c. | Figure 4 | ||

d. | Figure 2 |

In the given figure, Figure 3 shows exactly one rectangular array.

So, the array represented in Figure 3 shows a prime number.

Correct answer : (1)