The average rate of change of f(x) on the interval [a,b] is f(b)−f(a)/b−a.
We have that a=1, b=5, f(x)=5⋅2^x.
Thus, f(b)−f(a)/b−a = 5⋅2(5)−(5⋅2(1))/5−(1) = 75/2
Answer: The average rate of change is 75/2 = 37.5.
Hopefully this helps.
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