SOLUTION
We have been given a graph that shows numbers of servings (y) in different amounts (x) of frozen yogurt listed on a carton.
To write an equation that gives the number of servings y in x pints, we will have to find the slope (rate of change) of our given linear function.
Since we know that rate of change of a function can be found by vertical change of the function divided by horizontal change of the function.
We pick any two point in the graph given, consider the image below

Substitute into the formula and obtain the slope

Hence the equation is of the form

since
m=2.5 and c=0,
The equation that gives the number of servings y in x pints is y=2.5x