Identify and explain ratios and rates in familiar situations (e.g., cost per music download, traditional mixtures for bleaching, time for a hand-sized piece of fungus to burn, mixing of colours, number of boys to girls at a school dance, rates of traveling such as car, skidoo, motor boat or canoe, fishing nets and expected catches, or number of animals hunted and number of people to feed).

Identify situations (such as providing for the family or community through hunting) in which a given quantity of a/b represents a:

• fraction
• rate
• quotient
• percent
• probability
• ratio.

Demonstrate (orally, through arts, concretely, pictorially, symbolically, and/or physically) the difference between ratios and rates.

Verify or contradict proposed relationships between the different roles for quantities that can be expressed in the form a/b. For example:

• a rate cannot be represented by a percent because a rate compares two different types of measurements while a percent compares two measurements of the same type
• probabilities cannot be used to represent ratios because probabilities describe a part to whole relationship but ratios describe a part to part relationship
• a fraction is not a ratio because a fraction represents part to whole
• a ratio cannot be written as a fraction, unless the quantity of the whole is first determined (e.g., 2 parts white and 5 parts red paint is 2/7 white)
• a ratio cannot be written as percent unless the quantity of the whole is first determined (e.g., a ratio of 4 parts blue and 6 parts red paint can be described as having 40% blue).

Write the symbolic form (e.g., 3:5 or 3 to 5 as a ratio, $3/{\min}$ or 3 per one minute as a rate) for a concrete, physical, or pictorial representation of a ratio or rate.

Explain how to recognize whether a comparison requires the use of proportional reasoning (ratios or rates) or subtraction.

Create and solve problems involving rates, ratios, and/or probabilities.