Mastering Multiplication and Division Skills
Year 7 Mathematics Revision Building Strong Number Skills Excel GCSE Preparation
Learning Objectives & Success Criteria
Master column method for multiplying integers Apply short division for dividing integers Multiply and divide by powers of 10, 0.1, and 0.01 Solve decimal multiplication and division Apply order of operations in complex problems Solve area problems using multiplication
Column Method for Multiplying Integers
Line up numbers by place value Start multiplying from the ones column Carry over when products exceed 9 Add partial products for final answer Example: 234 × 56
Practice: Column Multiplication
Solve: 123 × 45 Solve: 267 × 38 Solve: 456 × 72 Check your work with a partner
Short Division Method
Divide from left to right Write quotient above the dividend Carry remainders to next digit Check: quotient × divisor = dividend Example: 1248 ÷ 6
Powers of 10: Patterns and Rules
{"left":"Multiplying by 10: Move decimal point 1 place right\nMultiplying by 100: Move decimal point 2 places right\nMultiplying by 1000: Move decimal point 3 places right","right":"Dividing by 10: Move decimal point 1 place left\nDividing by 100: Move decimal point 2 places left\nDividing by 1000: Move decimal point 3 places left"}
Quick Check: Powers of 10
What is 45.6 × 100? What is 3400 ÷ 10? What is 0.78 × 1000? Explain the pattern you notice
Multiplying and Dividing by 0.1 and 0.01
Multiplying by 0.1 = dividing by 10 Multiplying by 0.01 = dividing by 100 Dividing by 0.1 = multiplying by 10 Dividing by 0.01 = multiplying by 100 Example: 56 × 0.1 = 5.6
Multiplying Decimals
Ignore decimal points initially Multiply as whole numbers Count total decimal places in both numbers Place decimal point in answer Example: 2.4 × 1.3
Decimal Operations Challenge
Calculate: 3.2 × 0.1 Calculate: 4.5 ÷ 0.01 Calculate: 1.6 × 2.5 Which method did you use for each?
Dividing Decimals
Make divisor a whole number Move decimal point same amount in dividend Divide normally Place decimal point directly above Example: 12.6 ÷ 1.4
Mathematical Thinking
'Mathematics is not about numbers, equations, computations, or algorithms: it is about understanding.' - William Paul Thurston
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