Whole Numbers
Properties of whole numbers, number line, and predecessor-successor.
Chapter Overview
Whole numbers are 0, 1, 2, 3, ... They extend natural numbers by including zero. This chapter covers predecessor, successor, number line, and properties of addition and multiplication.
Predecessor and Successor
- Successor of n is n + 1
- Predecessor of n is n − 1 (not defined for 0)
- 0 is the smallest whole number
Number Line
- Whole numbers are marked at equal intervals starting from 0
- Addition moves right; subtraction moves left
- Multiplication as repeated addition on the number line
Properties
Closure
a + b and a × b are whole numbers
Commutative
a + b = b + a; a × b = b × a
Associative
(a + b) + c = a + (b + c)
Distributive
a × (b + c) = a×b + a×c
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Example 1: Successor and Predecessor
Find successor and predecessor of 5,89,432.
- 1Successor = 5,89,432 + 1
- 2Predecessor = 5,89,432 − 1
Answer
Successor: 5,89,433; Predecessor: 5,89,431
Example 2: Properties
Verify commutative property: 347 + 528 = 528 + 347.
- 1347 + 528 = 875
- 2528 + 347 = 875
Answer
Both equal 875 — commutative property holds.
Key Points to Remember
- ✓ Zero is a whole number but not a natural number
- ✓ Division is not always closed for whole numbers
- ✓ Identity for addition is 0; for multiplication is 1
Exam Tips
- • State the property name when asked to verify
- • Use number line for visual addition/subtraction
Practice MCQs — Whole Numbers
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Predecessor of 0 is: