Group Activity Cards
Patterns
and
Functions
Number of players: 2
Materials: Grid paper

The Price Is Right 
Copy the section of a coordinate plane shown below.
You may have heard someone say that one thing is a function of another thing. This means that there is a function rule that describes the relationship between the two things.
The number of cups of hot chocolate you will buy may be a function of the weather outside, but definitely is a function of the price of one cup. Suppose the function rule that describes the relationship between the number of cups a person will buy and any given price is n = 5  2p. Graph this function.
Suppose that you decide to open a hotchocolate stand. You can use the graph you made to decide how much to charge to make the most money. Choose any point on the line. Find the ordered pair that names this point. Then find the product of the ordered pairs. This tells you the amount of money for y cups purchased at a price of x dollars. Find the ordered pair with the greatest product. How much will you charge for a cup? How many cups will the average person buy at this price?
