The following graph shows the populations of the metropolitan areas of City X and City Y over six years.
-If equations of the form y = f(t) were determined that modeled either of the two graphs, then the variable t would represent and the variable y would represent .
A) population (in millions); year
B) City X; City Y
C) City Y; City X
D) year; population (in millions)

Question

The following graph shows the populations of the metropolitan areas of City X and City Y over six years. 
-If equations of the form y = f(t) were determined that modeled either of the two graphs, then the variable t would represent and the variable y would represent .
A) population (in millions); year 
B) City X; City Y 
C) City Y; City X 
D) year; population (in millions)

Quizplus · Accepted Answer

In equations of the form y = f(t), typically, t represents the independent variable (time, in many cases), and y represents the dependent variable (what is being measured or predicted, such as population). Thus, "year" would be a natural choice for t, and "population (in millions)" for y.

The Following Graph Shows the Populations of the Metropolitan Areas