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Number Systems (9 Mathematics)

Number systems encompass natural numbers, whole numbers, integers, rational, and irrational numbers. Understanding the properties and representation of the

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TL;DR: Number systems encompass natural numbers, whole numbers, integers, rational, and irrational numbers. Understanding the properties and representation o…

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Number systems encompass natural numbers, whole numbers, integers, rational, and irrational numbers. Understanding the properties and representation of the

Number Systems MCQs with Answers & Explanations

Q1. Which of the following is a whole number but not a natural number?

  1. 1
  2. 0 ✓ (correct)
  3. -1
  4. 2

Q2. A rational number can be expressed as:

  1. p × q
  2. p ÷ q where q = 0
  3. p/q where p and q are integers and q ≠ 0 ✓ (correct)
  4. √(p/q)

Q3. √9 is:

  1. Irrational
  2. Rational ✓ (correct)
  3. Neither rational nor irrational
  4. Not a real number

Q4. Which of the following is an irrational number?

  1. √4
  2. √9
  3. √10 ✓ (correct)
  4. √16

Q5. The decimal representation of 1/6 is:

  1. 0.16
  2. 0.1̄6̄
  3. 0.1666... ✓ (correct)
  4. 0.166

Q6. On a number line, integers are:

  1. Only positive numbers
  2. Only on one side of zero
  3. Symmetrically placed about zero ✓ (correct)
  4. Not equally spaced

Q7. Which set of numbers is closed under subtraction?

  1. Natural numbers
  2. Whole numbers
  3. Integers ✓ (correct)
  4. Rational numbers

Q8. The set {-2, -1, 0, 1, 2} represents:

  1. Natural numbers
  2. Whole numbers
  3. Integers ✓ (correct)
  4. Rational numbers

Q9. Which of the following is NOT a real number?

  1. √-1 ✓ (correct)
  2. √2
  3. 0
  4. π

Q10. The decimal expansion of 22/7 is:

  1. 3.14
  2. 3.142857142857... ✓ (correct)
  3. 3.1̄4̄2̄8̄5̄7̄
  4. Non-terminating and non-repeating

Frequently Asked Questions

How are rational and irrational numbers different?

Rational numbers can be expressed as p/q (where p, q are integers and q ≠ 0) and have terminating or repeating decimal expansions. Irrational numbers cannot be expressed as fractions and have non-terminating, non-repeating decimal expansions.

What is the difference between natural numbers and whole numbers?

Natural numbers start from 1 and include {1, 2, 3, ...}. Whole numbers include zero and all natural numbers: {0, 1, 2, 3, ...}. The main difference is that whole numbers include zero.

More 9 Mathematics MCQs

  • Coordinate Geometry
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  • Trigonometry (Applications Case Study)
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