ANSWER
Function 1 has a greater rate of change
Step-by-step explanation
We have two functions in the question.
and
The rate of change of a function is defined as the slope or gradient of the function.
Linear functions (such as these) have a general form:
y = mx + c
where m = slope/gradient
c = y intercept
By comparing, we see that:
For function 1, m = 3
For function 2, m = 1/3
Therefore, the gradient (rate of change) of function 1 is greater than that of function 2.