Number System for JNV Entrance Test | JNVS Exam 2025

 

Number System for JNV Entrance Test

The Number System is an important topic for the JNV Entrance Test. It is essential to understand the different types of numbers, their properties, and how to perform basic arithmetic operations on them. This topic covers various concepts such as types of numbers, place value system, operations, and number theory. Below is an overview of the number system, followed by MCQs to help you prepare effectively for the exam.

Key Concepts of Number System

1. Natural Numbers:
   Natural numbers are the basic numbers we use to count things. They start from 1 and go on indefinitely, i.e., 1, 2, 3, 4, 5, ….

   • Example: The number of apples in a basket can be expressed as a natural number.

2. Whole Numbers:
   Whole numbers include all natural numbers plus 0.

   • Example: 0, 1, 2, 3, 4, …

3. Integers:
   Integers are a broader set of numbers that include positive whole numbers, negative whole numbers, and 0.

   • Example: -2, -1, 0, 1, 2, 3, …

4. Rational Numbers:
   Rational numbers are numbers that can be expressed in the form of p/q, where p and q are integers, and q ≠ 0.

   • Example: 1/2, -3/4, 5/7.

5. Irrational Numbers:
   These numbers cannot be expressed as a fraction of integers. Their decimal representation goes on forever without repeating.

   • Example: √2, π, e.

6. Real Numbers:
   Real numbers consist of both rational and irrational numbers. All the numbers we commonly use are real numbers.

   • Example: 5, -3/2, 2.5, √3.

7. Prime Numbers:
   Prime numbers are numbers greater than 1 that have only two factors: 1 and the number itself.

   • Example: 2, 3, 5, 7, 11, 13.

8. Composite Numbers:
   Composite numbers have more than two factors.

   • Example: 4, 6, 8, 9, 10.

9. Even and Odd Numbers:

   • Even Numbers: Numbers divisible by 2.

     • Example: 2, 4, 6, 8.

   • Odd Numbers: Numbers not divisible by 2.

     • Example: 1, 3, 5, 7.

10. Perfect Squares:
    A perfect square is a number that can be expressed as the square of an integer.

• Example: 1, 4, 9, 16.

11. Place Value System:
    The place value system is the system by which we define the position of each digit in a number. In the number 1234, the place values of the digits are:

• 1 (thousands)

• 2 (hundreds)

• 3 (tens)

• 4 (ones)

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Multiple Choice Questions (MCQs)

1. Which of the following is a natural number?

• a) 0

• b) -5

• c) 8

• d) -3.5

Answer: c) 8

2. Which of the following is a rational number?

• a) √3

• b) π

• c) 7/8

• d) √2

Answer: c) 7/8

3. What is the value of 5 × 10^3?

• a) 5000

• b) 500

• c) 50

• d) 50000

Answer: a) 5000

4. Which of the following numbers is a prime number?

• a) 4

• b) 6

• c) 13

• d) 9

Answer: c) 13

5. Which of the following is not an integer?

• a) -3

• b) 0

• c) 2.5

• d) 5

Answer: c) 2.5

6. Which of the following numbers is a perfect square?

• a) 7

• b) 16

• c) 18

• d) 10

Answer: b) 16

7. Which of the following is the smallest prime number?

• a) 0

• b) 1

• c) 2

• d) 3

Answer: c) 2

8. Which of the following is an irrational number?

• a) 2/3

• b) √4

• c) 0.75

• d) √5

Answer: d) √5

9. Which of the following numbers is both even and prime?

• a) 4

• b) 2

• c) 6

• d) 8

Answer: b) 2

10. What is the value of (4 × 10^2) ÷ (2 × 10^1)?

• a) 20

• b) 2

• c) 200

• d) 0.2

Answer: b) 2

11. Which of the following is a composite number?

• a) 3

• b) 5

• c) 9

• d) 11

Answer: c) 9

12. What is the decimal representation of 7/8?

• a) 0.75

• b) 0.875

• c) 1.25

• d) 0.65

Answer: b) 0.875

13. Which of the following is an even number?

• a) 11

• b) 7

• c) 14

• d) 3

Answer: c) 14

14. The smallest three-digit number is:

• a) 100

• b) 101

• c) 1

• d) 0

Answer: a) 100

15. What is the sum of the first five prime numbers?

• a) 28

• b) 18

• c) 30

• d) 20

Answer: a) 28

16. Which of the following is not a rational number?

• a) 0.3333...

• b) 2/5

• c) √2

• d) 1.25

Answer: c) √2

17. What is the square root of 25?

• a) 5

• b) 6

• c) 25

• d) 2.5

Answer: a) 5

18. Which of the following is a multiple of 6?

• a) 12

• b) 8

• c) 7

• d) 10

Answer: a) 12

19. What is the product of the first three prime numbers?

• a) 30

• b) 60

• c) 15

• d) 10

Answer: a) 30

20. Which of the following numbers is divisible by 3?

• a) 15

• b) 22

• c) 17

• d) 14

Answer: a) 15

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Summary of Key Takeaways

• The Number System is fundamental to understanding mathematics.

• It includes various types of numbers such as natural numbers, whole numbers, integers, rational, and irrational numbers.

• Prime numbers have only two factors: 1 and the number itself.

• Even numbers are divisible by 2, while odd numbers are not.

• Place value defines the value of each digit in a number based on its position.

• Mastering the number system involves understanding how to categorize numbers, their operations, and applying this knowledge to solve problems.

Conclusion

The Number System is a key area in the JNV Entrance Test, with questions ranging from basic arithmetic to number properties. Understanding the types of numbers, their characteristics, and their operations will significantly improve your chances of performing well in the exam. By practicing the MCQs above, you will develop a strong foundation in the topic and be well-prepared for the test.