1. Section 6.5.1 – Ratio, Proportion, Variation The Vocabulary

2. y varies directly as x y varies inversely as x y varies jointly as x and z y is (directly) proportional to x y is inversely proportional to x y is jointly proportional to x and z k – constant of variation/proportionality

3. Using the constant ‘k’ and the given information, create a mathematical model for: The total (t) varies inversely as the square of its parts (p) Using the constant ‘k’ and the given information, create a mathematical model for: The simple interest (I) on an investment is proportional to the amount of the investment (P).

4. Using the constant ‘k’ and the given information, create a mathematical model for: The distance (d) a spring is stretched (or compressed) varies directly as the force (F) on the spring. Using the constant ‘k’ and the given information, create a mathematical model for: The volume (v) varies directly as the cube of an edge (e).

5. Using the constant ‘k’ and the given information, create a mathematical model for: The height (h) of an object varies inversely as the square root of its width (w). Using the constant ‘k’ and the given information, create a mathematical model for: The length (L) of an object is jointly proportional to the square of its width (w) and the cube of its height (h).

6. Using the constant ‘k’ and the given information, create a mathematical model for: The stopping distance (d) of an automobile is directly proportional to the square of its speed (s). Using the constant ‘k’ and the given information, create a mathematical model for: The intensity (I) of a sound wave varies jointly as the square of its frequency (f) and the speed of sound (v) and inversely as the square of its amplitude (r).