A recipe for 3 cups of snack mix calls for 1··2cup of pretzels. You can describe this as 3 cups of snack mix for every 1··2cup of pretzels and as 1··2cup of pretzels for every 3 cups of snack mix. Why? How could you describe the relationship in terms of 1 cup of pretzels? What is this constant of proportionality?
How could you describe the relationship in terms of 1 cup of snack mix? What is this constant of proportionality?
Why are the two constants of proportionality not the same?