We have to calculate the future value (FV) after n = 18 years of an investment of $142 each year, with a rate of interest of 4.6% (r = 0.046) compounded annually.
We can calculate the future value of an annuity like this as:
[tex]FV=P\cdot\frac{(1+r)^n-1}{i}[/tex]Replacing and calculating, we get:
[tex]\begin{gathered} FV=142\cdot\frac{(1+0.046)^{18}-1}{0.046} \\ FV=142\cdot\frac{1.046^{18}-1}{0.046} \\ FV\approx142\cdot\frac{2.24683-1}{0.046} \\ FV\approx142\cdot\frac{1.24683}{0.046} \\ FV\approx142\cdot27.1 \\ FV\approx3848.91 \end{gathered}[/tex]Answer: She will have $3848.91 in her account.