π Mathematical Fundamentals
Commutative Property
Addition and multiplication are commutative: a + b = b + a and a Γ b = b Γ a.
Order doesn't matter for these operations.
Associative Property
Addition and multiplication are associative: (a + b) + c = a + (b + c) and (a Γ b) Γ c = a Γ (b Γ c).
Grouping doesn't matter.
Distributive Property
Multiplication distributes over addition: a Γ (b + c) = (a Γ b) + (a Γ c).
This is fundamental for algebra.
Identity Elements
0 is the additive identity (a + 0 = a) and 1 is the multiplicative identity (a Γ 1 = a).
These numbers don't change other numbers.
Inverse Operations
Addition and subtraction are inverse operations, as are multiplication and division.
They "undo" each other.
Order of Operations
Follow PEMDAS: Parentheses, Exponents, Multiplication/Division (left to right), Addition/Subtraction (left to right).
π‘ Step-by-Step Examples
347 + 289 = ?
- Step 1: Align numbers by place value
- Step 2: Add ones place: 7 + 9 = 16 (write 6, carry 1)
- Step 3: Add tens place: 4 + 8 + 1 = 13 (write 3, carry 1)
- Step 4: Add hundreds place: 3 + 2 + 1 = 6
- Result: 347 + 289 = 636
523 - 187 = ?
- Step 1: Align numbers by place value
- Step 2: Ones place: 3 - 7 requires borrowing
- Step 3: Borrow from tens: 13 - 7 = 6
- Step 4: Tens place (after borrowing): 1 - 8 requires borrowing
- Step 5: Borrow from hundreds: 11 - 8 = 3
- Step 6: Hundreds place: 4 - 1 = 3
- Result: 523 - 187 = 336
34 Γ 26 = ?
- Step 1: Multiply 34 Γ 6 = 204
- Step 2: Multiply 34 Γ 20 = 680
- Step 3: Add partial products: 204 + 680
- Step 4: Calculate sum: 884
- Result: 34 Γ 26 = 884
756 Γ· 18 = ?
- Step 1: How many times does 18 go into 75? Answer: 4
- Step 2: 4 Γ 18 = 72, subtract: 75 - 72 = 3
- Step 3: Bring down 6 to make 36
- Step 4: How many times does 18 go into 36? Answer: 2
- Step 5: 2 Γ 18 = 36, subtract: 36 - 36 = 0
- Result: 756 Γ· 18 = 42
2βΆ = ?
- Step 1: 2βΆ means 2 Γ 2 Γ 2 Γ 2 Γ 2 Γ 2
- Step 2: 2 Γ 2 = 4
- Step 3: 4 Γ 2 = 8
- Step 4: 8 Γ 2 = 16
- Step 5: 16 Γ 2 = 32
- Step 6: 32 Γ 2 = 64
- Result: 2βΆ = 64
β144 = ?
- Step 1: Find what number multiplied by itself equals 144
- Step 2: Try perfect squares: 10Β² = 100 (too small)
- Step 3: Try 12Β²: 12 Γ 12
- Step 4: Calculate: 12 Γ 12 = 144
- Step 5: Verify: 12 Γ 12 = 144 β
- Result: β144 = 12
π Real-World Applications
Use addition to sum income sources, subtraction for expenses, multiplication for repeated payments,
and division for average calculations. Essential for budgeting and financial planning.
Calculate material quantities, room areas, paint coverage, and project costs.
Multiplication and division are crucial for scaling measurements and estimating materials.
Scale recipes up or down using multiplication and division. Calculate cooking times,
ingredient ratios, and nutritional values for meal planning.
Calculate grades, averages, percentages, and test scores.
Essential for academic progress tracking and standardized test preparation.