In the real world, functions are mathematical representations of input-output situations. A vending machine is one such example. The input is the money combined with the selected button. The output is the product.

Here is another example: The formula for converting a temperature from Fahrenheit to Celsius is a function expressed as:

C = (5/9)*(F - 32), where F is the Fahrenheit temperature and C is the Celsius temperature.

If it is 77 degrees Fahrenheit in Phoenix Arizona, then what is the equivalent temperature on the Celsius thermometer?

Our input is 77.

C = (5/9)*(77 - 32)

C = (5/9)*(45)

C = 25

The equivalent temperature is 25 degrees Celsius.

Choose your own function or choose from the list below and then provide a unique example of a function and evaluate the function for a specific input (like the example above).

The circumference of a circle is a function of diameter.

The height of a tree is a function of its age.

The length of person's shadow on the ground is a function of his or her height.

Weekly salary is a function of the hourly pay rate and the number of hours worked.

Compound interest is a function of initial investment, interest rate, and time.

Supply and demand: As price goes up, demand goes down.