Answer:
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Continuous compounding equation:
- [tex]P(t) = P_0e^{rt}[/tex]
Given
- [tex]P_0=36000[/tex]
- [tex]P(t)=39.876.15[/tex]
- [tex]t=2.5[/tex]
Find the value of r
- [tex]39786.15= 36000*e^{r*2.5}[/tex]
- [tex]e^{2.5r}=39786.15/36000[/tex]
- [tex]ln \ e^{2.5r}= ln \ 1.10517[/tex]
- [tex]2.5r=0.099[/tex]
- [tex]r=0.099/2.5[/tex]
- [tex]r=0.04[/tex]
Now find the time t for the balance to grow to $51806.67:
- [tex]51806.67= 36000*e^{0.04t}[/tex]
- [tex]51806.67/36000=e^{0.04t}[/tex]
- [tex]e^{0.04t}= 1.439[/tex]
- [tex]ln \ e^{0.04t}= ln \ 1.439[/tex]
- [tex]0.04t=0.3639[/tex]
- [tex]t=0.3639/0.04[/tex]
- [tex]t=9.0975[/tex]
The time required is about 9 years.