Answer:
[tex]V = 500(1-0.7)^{4}[/tex]
or
[tex]V = 500(0.3)^{4}[/tex]
Step-by-step explanation:
The value of her phone after t intervals of 6 months is given by the following equation:
[tex]V(t) = V(0)(1-r)^{t}[/tex]
In which V(0) is the initial value and r is the depreciation rate, as a decimal.
Last month, Maria purchased a new cell phone for $500.
This means that [tex]V(0) = 500[/tex]
The store manager told her that her new cell phone would depreciate by 70% every 6 months.
This means that [tex]r = 0.7[/tex]
So
[tex]V(t) = V(0)(1-r)^{t}[/tex]
[tex]V(t) = 500(1-0.7)^{t}[/tex]
[tex]V(t) = 500(0.3)^{t}[/tex]
After 2 years:
2 years is 24 months, 24/6 = 4, so we have to find V(4).
The possible options are:
[tex]V = 500(1-0.7)^{4}[/tex]
or
[tex]V = 500(0.3)^{4}[/tex]