SSC CGL Number System Verified Practice Test 1
15 structurally validated Number System questions with unique options, mapped answers and explanations.
SSC CGL Number System Verified Practice Test 1
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 1 (no login required)
- HCF
1. What is the HCF of 24 and 36?
- A. 6
- B. 8
- C. 10
- D. 12 (Correct)
Explanation: 12 is the greatest number that divides both 24 and 36 exactly.
- LCM
2. The LCM of 12 and 15 is:
- A. 30
- B. 45
- C. 60 (Correct)
- D. 90
Explanation: LCM of 12 and 15 is 60.
- Divisibility
3. Which of the following is divisible by 9?
- A. 234
- B. 243 (Correct)
- C. 256
- D. 271
Explanation: Sum of digits of 243 is 9, so it is divisible by 9.
- Remainders
4. What is the remainder when 125 is divided by 7?
- A. 4
- B. 5
- C. 6 (Correct)
- D. 3
Explanation: 7 × 17 = 119, so the remainder is 6.
- Factors
5. How many factors does 36 have?
- A. 6
- B. 8
- C. 9 (Correct)
- D. 10
Explanation: 36 = 2^2 × 3^2, so number of factors = (2+1)(2+1) = 9.
- Prime Numbers
6. Which of the following is a prime number?
- A. 21
- B. 27
- C. 29 (Correct)
- D. 35
Explanation: 29 has no positive divisors other than 1 and 29.
- Multiples
7. The least number divisible by 3, 4 and 5 is:
- A. 30
- B. 40
- C. 50
- D. 60 (Correct)
Explanation: The least number divisible by 3, 4, and 5 is their LCM, 60.
- Divisibility
8. A number is divisible by 11 if:
- A. Sum of digits is 11
- B. Last digit is 1
- C. Difference of sums of alternate digits is divisible by 11 (Correct)
- D. It is even
Explanation: That is the divisibility rule for 11.
- Remainders
9. When a number is divided by 5, the possible remainders are:
- A. 1 to 5
- B. 0 to 4 (Correct)
- C. 0 to 5
- D. 1 to 4
Explanation: For division by 5, remainders can only be 0, 1, 2, 3, or 4.
- HCF and LCM
10. If HCF of two numbers is 6 and their LCM is 180, and one number is 30, the other number is:
- A. 36 (Correct)
- B. 42
- C. 48
- D. 54
Explanation: Product of numbers = HCF × LCM = 6 × 180 = 1080. Other number = 1080 / 30 = 36.
- Even and Odd
11. The product of two odd numbers is always:
- A. Even
- B. Odd (Correct)
- C. Prime
- D. Zero
Explanation: Odd × odd is always odd.
- Perfect Squares
12. Which of the following is a perfect square?
- A. 196 (Correct)
- B. 198
- C. 202
- D. 218
Explanation: 196 = 14^2, so it is a perfect square.
- Unit Digit
13. The unit digit of 7^4 is:
- A. 1 (Correct)
- B. 3
- C. 7
- D. 9
Explanation: 7^2 = 49 and 7^4 = 2401, so the unit digit is 1.
- Successive Division
14. If a number leaves remainder 2 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 ≡ 2 (mod 5), then n^2 ≡ 4 (mod 5).
- Divisibility
15. Which of the following is divisible by 3?
- A. 451
- B. 572
- C. 684 (Correct)
- D. 701
Explanation: 6 + 8 + 4 = 18, which is divisible by 3.