Number Foundations
Master whole numbers, integers, and order of operations
Learning Objectives
- Apply order of operations (BODMAS) correctly
- Work confidently with negative numbers
- Round and estimate to check answers quickly
- Understand place value in large and decimal numbers
- Solve real-world number problems in teaching contexts
1. Place Value & Number Sense
Place Value Breakdown
Understanding place value is the foundation of numeracy. Each digit in a number has a value based on its position: ones, tens, hundreds, thousands, and decimal places like tenths and hundredths.
ACER Authentic Problem: Ordering Numbers and Place Value
Reading Fluency Scores: Student A = 3.14, Student B = 3.2, Student C = 3.015, Student D = 3.104.
2. Operations with Whole Numbers
The Four Basic Operations
Mastering addition (+), subtraction (-), multiplication (×), and division (÷) without relying on a calculator is essential for the LANTITE exam.
ACER Authentic Problem: Multi-Item Budgeting & Change (Sept 2023 Q7)
PAYING FOR DINNER
Kim and Lee meet for dinner. Kim has a burger for $15.90 and Lee has a salad for $14.90. They each have a drink costing $4.00 each.
Keywords for Operations
| Addition (+) | Subtraction (-) | Multiplication (×) | Division (÷) |
|---|---|---|---|
| Sum, altogether | Difference, fewer | Product, times | Quotient, average |
| Combined, plus | Remaining, less than | Each, per, groups of | Share, split, per person |
3. Order of Operations (BODMAS)
What is BODMAS?
BODMAS stands for Brackets, Orders (powers/roots), Division, Multiplication, Addition, and Subtraction. It tells you the correct sequence to solve mathematical expressions.
The BODMAS Rule
Step-by-step BODMAS Calculation
Nested Brackets Calculation
4. Negative Numbers & Integers
Understanding Integers
Integers include all whole positive and negative numbers, including zero. Think of them visually on a number line to help with addition and subtraction.
Adding and Subtracting Negative Numbers
5. Rounding & Estimation
Rounding Rules
Look at the digit immediately to the right of your target place value. If it is 5 or above, round up. If it is 4 or below, keep the target digit the same (round down).
ACER Authentic Problem: Car Speedometer Scale (July 2017 Q1)
CAR SPEEDO
This speedometer shows the speed at which a car is travelling.
CAR SPEEDOMETER
Posted Speed Limit: 110 km/h
6. Solving Word Problems
Word Problem Strategy
Tackle word problems step-by-step: Read carefully, Identify the key information, Plan your approach (choose operation), Solve, and Check if the answer makes sense in context.
ACER Authentic Problem: School Day Duration (July 2017 Q2)
CLASS TIME
ACER 2017 Q1: The speedometer needle indicates 122 km/h. If the speed limit is 110 km/h, what is the difference between the speed limit and the speed shown?
