Name: ______________________________ Date: _____________ Period: _____
The Vending Machine: A school cafeteria contains a vending machine which sells drinks.
On a typical day:
 The machine starts half full.
 No drinks are sold before 7 am or after 5 pm.
 Drinks are sold at a slow rate throughout the day, except during lunch and for a
period of time after school. There is a greater demand during these times.
o 1st Lunch: 11:00 to 1:00 pm
o After School: 2:30 – 3:30 pm
 The machine is filled up right before lunch at a constant rate. It takes about 30
minutes to fill the machine.
Sketch a graph that shows the number of drinks in the machine as a function of the time
of day from 6 am to 6 pm.
Create a table of the data.
Adapted from a problem in the book The Language of Functions and Graphs by the Shell Centre for
Mathematical Education