MCQs on Prime and Composite Numbers – Class 6
MCQs on Prime and Composite Numbers – Class 6
Class: 6 | Subject: Mathematics | Chapter: 3 – Number Play | Topic: Prime & Composite Numbers
CBSE Board Examination Practice
CBSE Board Examination Practice
Instructions: These MCQs are strictly based on the CBSE curriculum and NCERT books, ideal for Class 6 Mathematics exam preparation.
1. A prime number has exactly:
Answer: B) Two factors
Explanation: A prime number has only two factors – 1 and itself.
Explanation: A prime number has only two factors – 1 and itself.
2. Which of the following is a prime number?
Answer: C) 17
Step: Check divisibility → 17 is divisible only by 1 and 17.
Step: Check divisibility → 17 is divisible only by 1 and 17.
3. Which is a composite number?
Answer: C) 21
Step: 21 = 3 × 7 → More than two factors.
Step: 21 = 3 × 7 → More than two factors.
4. The number 1 is:
Answer: D) Neither prime nor composite
5. Smallest prime number is:
Answer: C) 2
6. Smallest composite number is:
Answer: C) 4
7. Which pair consists of prime numbers?
Answer: B) 11, 13
8. How many prime numbers are there between 1 and 10?
Answer: B) 4
Step: 2, 3, 5, 7 → Four primes.
Step: 2, 3, 5, 7 → Four primes.
9. 25 is:
Answer: B) Composite
25 = 5 × 5.
25 = 5 × 5.
10. Which number has exactly three factors?
Answer: A) 4
Factors: 1, 2, 4.
Factors: 1, 2, 4.
11. 29 is:
Answer: A) Prime
12. Which is not a prime number?
Answer: C) 39
39 = 3 × 13.
39 = 3 × 13.
13. The only even prime number is:
Answer: A) 2
14. 51 is composite because:
Answer: B) It has more than two factors
51 = 3 × 17.
51 = 3 × 17.
15. Total factors of a prime number are:
Answer: B) 2
16. 49 is:
Answer: B) Composite
49 = 7 × 7.
49 = 7 × 7.
17. Prime numbers less than 20 are:
Answer: A
18. 77 is composite because:
Answer: A) 7 × 11
19. Which is prime?
Answer: B) 97
20. Composite numbers have:
Answer: C) More than two factors
