SSC CGL Number System Verified Practice Test 3
15 structurally validated Number System questions with unique options, mapped answers and explanations.
SSC CGL Number System Verified Practice Test 3
15 structurally validated Number System questions with unique options, mapped answers and explanations.
Preview all 15 questions in SSC CGL Number System Verified Practice Test 3 (no login required)
- LCM
1. LCM of 9 and 12 is:
- A. 18
- B. 24
- C. 36 (Correct)
- D. 72
Explanation: LCM of 9 and 12 is 36.
- HCF
2. HCF of 56 and 72 is:
- A. 4
- B. 6
- C. 8 (Correct)
- D. 12
Explanation: 8 is the greatest common divisor of 56 and 72.
- Unit Digit
3. The unit digit of 2^9 is:
- A. 2 (Correct)
- B. 4
- C. 6
- D. 8
Explanation: Powers of 2 repeat 2, 4, 8, 6. 9 mod 4 = 1, so unit digit is 2.
- Even and Odd
4. Odd + odd is always:
- A. Even (Correct)
- B. Odd
- C. Prime
- D. Composite
Explanation: Sum of two odd numbers is always even.
- Remainders
5. If a number leaves remainder 3 when divided by 5, what remainder will its square leave when divided by 5?
- A. 1
- B. 2
- C. 3
- D. 4 (Correct)
Explanation: If n ≡ 3 (mod 5), then n^2 ≡ 9 ≡ 4 (mod 5).
- Divisibility
6. A number divisible by 8 must have its last three digits divisible by:
- A. 2
- B. 4
- C. 8 (Correct)
- D. 16
Explanation: Divisibility by 8 depends on the last three digits.
- Prime Factorization
7. Prime factorization of 90 is:
- A. 2 x 3^2 x 5 (Correct)
- B. 2^2 x 3 x 5
- C. 3^2 x 5^2
- D. 2 x 3 x 5^2
Explanation: 90 = 2 x 3 x 3 x 5.
- Unit Digit
8. The unit digit of 4^8 is:
- A. 2
- B. 4
- C. 6 (Correct)
- D. 8
Explanation: Powers of 4 alternate between 4 and 6; even powers end in 6.
- Divisibility
9. Which of the following numbers is divisible by 9?
- A. 234 (Correct)
- B. 245
- C. 256
- D. 268
Explanation: The digit sum of 234 is 9, so it is divisible by 9.
- Remainder
10. What is the remainder when 97 is divided by 8?
- A. 1 (Correct)
- B. 2
- C. 3
- D. 4
Explanation: 97 = 8 x 12 + 1.
- Prime Numbers
11. Which of these is a prime number?
- A. 39
- B. 51
- C. 53 (Correct)
- D. 57
Explanation: 53 has no divisor other than 1 and itself.
- LCM
12. LCM of 12 and 18 is:
- A. 24
- B. 30
- C. 36 (Correct)
- D. 48
Explanation: Prime factorization gives LCM = 2^2 x 3^2 = 36.
- HCF
13. HCF of 24 and 54 is:
- A. 4
- B. 6 (Correct)
- C. 8
- D. 12
Explanation: The greatest common divisor of 24 and 54 is 6.
- Remainder
14. If a number leaves remainder 5 when divided by 11, what remainder will it leave when 22 is added to it and divided by 11?
- A. 0
- B. 3
- C. 5 (Correct)
- D. 7
Explanation: Adding 22 adds two full multiples of 11, so the remainder stays 5.
- Digit Sum
15. The sum of digits of the number 58739 is:
- A. 30
- B. 31
- C. 32 (Correct)
- D. 33
Explanation: 5 + 8 + 7 + 3 + 9 = 32.