Answer:
1. 45 dollars per year.
2. 49.73 dollars per year.
3. 56.6 dollars per year.
4. Increases
Step-by-step explanation:
Average rate of change
The average rate of change of a function [tex]f(x)[/tex] over an interval [a,b] is given by:
[tex]A = \frac{f(b)-f(a)}{b-a}[/tex]
In this question, we have that:
[tex]A(t) = 900(1.05)^t[/tex]
1. What is the average rate of change for the first year?
[tex]A(0) = 900(1.05)^0 = 900[/tex]
[tex]A(1) = 900(1.05)^1 = 945[/tex]
So
[tex]A = \frac{A(1)-A(0)}{1-0} = \frac{945-900}{1-0} = 45[/tex]
45 dollars per year.
2. What is the average rate of change for the first five years?
[tex]A(0) = 900(1.05)^0 = 900[/tex]
[tex]A(5) = 900(1.05)^5 = 1148.65[/tex]
[tex]A = \frac{A(5)-A(0)}{5-0} = \frac{1148.65-900}{5-0} = 49.73[/tex]
49.73 dollars per year.
3. What is the average rate of change for the first ten years?
[tex]A(0) = 900(1.05)^0 = 900[/tex]
[tex]A(10) = 900(1.05)^{10} = 1466[/tex]
[tex]A = \frac{A(10)-A(0)}{10-0} = \frac{1466-900}{10-0} = 56.6[/tex]
56.6 dollars per year.
4. Does the average rate of change increase or decrease as time from the initial deposit gets longer?
From the previous items, it increases.