309960
Explanation
exponential decay function is a function that shrinks at a constant percent decay rate. The equation can be written in the form
[tex]\begin{gathered} y=a(1-b)^x \\ \text{where a is the initial cost} \\ b\text{ is the decrease percnetage ( in decimal)} \\ x\text{ is the time} \end{gathered}[/tex]so
Step 1
Let
[tex]\begin{gathered} a=605390 \\ b=20\text{ = 0.2} \\ x=\text{ 3 ( years)} \end{gathered}[/tex]replace
[tex]\begin{gathered} y=a(1-b)^x \\ y=605390(1-0.2)^3 \\ y=605390(0.8)^3 \\ y=605390(0.512) \\ y=309959.68 \\ \text{rounded to the whole number} \\ y=309960 \end{gathered}[/tex]therefore, the answer is
309960
I hope this helps you
