Computation and practical arithmetic
Key knowledge
• the order of operations, directed numbers, scientific notation, exact and approximate answers, significant figures and rounding
• orders of magnitude, units of measure that range over multiple orders of magnitude, and the concept of a log scale (base 10)
• concepts of ratio, proportion, percentage, percentage change and rate
• the unitary method.
Key skills
• distinguish between exact and approximate answers and write approximate answers correct to a given number of decimal places or significant figures
• use efficient mental and by-hand estimation and computation
• use technology effectively for computation
• use a log scale (base 10) to represent quantities that range over several orders of magnitude
• solve practical problems involving the use of ratios, proportions, percentages, percentage change, rates and the unitary method.
Financial arithmetic
Key knowledge
• concepts of simple and compound interest and their application
• cash flow in common savings and credit accounts including interest calculations
• compound interest investments and debts.
Key skills
• apply ratio and proportion, and percentage and percentage change, to solve problems in a range of financial
contexts
• apply simple interest to analyse cash flow in common savings and credit accounts
• apply compound interest to solve problems involving compound interest investments and loans
• compare the costs of a range of purchase options such as cash, credit and debit cards, personal loans, and time payments (hire purchase).