Answer: $ 42,607.34
Step-by-step explanation:
Formula to find the accumulated amount ( compounded continuously ):
[tex]A= Pe^{rt}[/tex]
,where P= principal amount
r= rate of interest
t= time
As per given , we have
A = $80,000
r= 3.5% = 0.035
t= 18 years
To find : P
Put all values in formula , we get
[tex]80000=Pe^{0.035\times18}\\\\\Rightarrow\ 80000=Pe^{0.63}\\\\\Rightarrow\ 80000=P(1.87761058)\\\\\Rightarrow\ P=\dfrac{80000}{1.87761057}\\\\\Rightarrow\ P=\dfrac{80000}{1.87761057}\\\\\Rightarrow\ P=42607.34[/tex]
Hence, $ 42,607.34 need to invest .
