**1. Which of the following is a prime number?**

a) 10

b) 17

c) 24

d) 33

**Answer:** b) 17

**Explanation:** 17 is a prime number. It has exactly two divisors, 1 and 17, and is not divisible by any other positive integer.

**2. Which of the following is not a prime number?**

a) 2

b) 3

c) 5

d) 6

**Answer:** d) 6

**Explanation:** 6 is not a prime number. It has more than two divisors, namely 1, 2, 3, and 6.

**3. Which of the following is a composite number?**

a) 11

b) 13

c) 15

d) 19

**Answer:** c) 15

**Explanation:** 15 is a composite number. It is divisible by 1, 3, 5, and 15.

**4. What is the smallest prime number greater than 10?**

a) 11

b) 13

c) 15

d) 17

**Answer:** a) 11

**Explanation:** The smallest prime number greater than 10 is 11, which has exactly two positive divisors (namely, 1 and 11).

**5. What is the largest prime number less than 20?**

a) 17

b) 19

c) 21

d) 23

**Answer:** b) 19

**Explanation:** The largest prime number less than 20 is 19, which has exactly two positive divisors (namely, 1 and 19).

**1. Which of the following is not a prime number?**

a) 23

b) 27

c) 29

d) 31

**Answer:** b) 27

**2. What is the sum of the first 10 prime numbers?**

a) 68

b) 129

c) 184

d) 223

**Answer:** b) 129

**3. What is the only even prime number?**

a) 1

b) 2

c) 3

d) 4

**Answer:** b) 2

**4. How many prime numbers are there between 50 and 70?**

a) 3

b) 4

c) 5

d) 6

**Answer:** b) 4 (53, 59, 61, 67)

**5. What is the sum of the prime numbers less than 10?**

a) 17

b) 26

c) 37

d) 50

**Answer:** a) 17

**6. Which of the following numbers is not prime?**

a) 19^{2} - 2

b) 27^{2} - 2

c) 31^{2} - 2

d) 37^{2} - 2

**Answer:** c) 31^{2} - 2

**7. What is the odd prime number?**

a) 13

b) 14

c) 15

d) 16

**Answer:** a) 13

**8. What is the next prime number after 89?**

a) 91

b) 93

c) 97

d) 99

**Answer:** c) 97

**9. Which of the following is a composite number?**

a) 31

b) 37

c) 41

d) 49

**Answer:** d) 49

**10. What is the next prime number after 11?**

a) 10

b) 12

c) 13

d) 14

**Answer:** c) 13

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