a Over the course of a day, a classroom will fill and empty as classes are held.
B
b Will the graph increase or decrease as tickets are sold?
C
c Will the graph increase or decrease over time as the athlete trains?
A
a Graph 3
B
b Graph 1
C
c Graph 4
Practice makes perfect
a Over the course of a school day, a classroom will fill and empty in intervals. This means the corresponding graph will show a graph that increases rapidly when the classroom fills and then sharply go down to zero as the classroom empties. The only graph that shows this behavior is Graph 3.
The little dips in the graph might reflect students who have to go to the bathroom or overlaps as classes change.
b When selling tickets to a concert there is usually a rush to buy tickets in the beginning, which means the number of tickets sold will increase sharply. However, as time passes and the die-hard fans have gotten their tickets, the number of sold tickets will level off. This behavior is reflected by Graph 1.
c When an athlete trains, the time he or she can run the 400 meter will get continuously better. This means that over time the graph will decrease. However, there is a natural limit to ones ability to run fast. This means the graph will at some point level off. This behavior is reflected by Graph 4.
