-32
Step-by-step explanation:
Step 1:
The rate of change over an interval is got by finding the change in g(x), the change in x and dividing it.
Step 2:
Given, x denotes the number of miles walked by Marcus for the fund raiser
g(x) denotes the amount of money he has left to raise after x miles of walking
g(x) for the interval [6,10] is 408,280
Change in x = 10-6 = 4
Change in g(x) = 280-408 = - 128
Rate of change = -128/4 = -32
Hence the average change in rate over the given interval is -32