Page 157 - The Ontario Curriculum, Grades 11 and 12: Mathematics, 2007

billed at a fixed cost per minute, where talking for half as many minutes costs half as much) and a situation involving a non-proportional relationship (e.g., cellular phone packages, where doubling the minutes purchased does not double the cost of the package; food pur- chases, where it can be less expensive to buy the same quantity of a product in one large package than in two or more small packages; hydro bills, where doubling consumption does not double the cost) in a personal and/or workplace context, and explain their reasoning
3.4 identify and describe the possible consequences (e.g., overdoses of medication; seized engines; ruined clothing; cracked or crumbling concrete) of errors in proportional reasoning (e.g., not recognizing the importance of maintaining proportionality; not correctly calculating the amount of each component in a mixture)
Sample problem: Age, gender, body mass, body chemistry, and habits such as smoking are some factors that can influence the effec- tiveness of a medication. For which of these factors might doctors use proportional rea- soning to adjust the dosage of medication? What are some possible consequences of making the adjustments incorrectly?
3.5 solve problems involving proportional reason- ing in everyday life (e.g., applying fertilizers; mixing gasoline and oil for use in small engines; mixing cement; buying plants for flower beds; using pool or laundry chemicals; doubling recipes; estimating cooking time from the time needed per pound; determining the fibre content of different sizes of food servings)
Sample problem: Bring the label from a large can of stew to class. Use the information on the label to calculate how many calories and how much fat you would consume if you ate the whole can for dinner. Then search out information on a form of exercise you could choose for burning all those calories. For what length of time would you need to exercise?
3.6 solve problems involving proportional reason- ing in work-related situations (e.g., calculating overtime pay; calculating pay for piecework; mixing concrete for small or large jobs)
Sample problem: Coiled pipe from the United States is delivered in 200-ft lengths. Your company needs pipe in 3.7-m sections. How many sections can you make from each 200-ft length?
APPLICATIONS OF MEASUREMENT
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Mathematics for Work and Everyday Life
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