Answer:
$804,680.814 ( approx )
Explanation:
The amount formula in compound interest is,
![A=P(1+(r)/(n))^(nt)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/44vs2zpmywawbh2b7k4ss2gheb6z49ybcd.png)
Where, P is the principal amount,
r is the annual rate of interest,
n is the compounding periods in a year,
t is the time in years,
Given, P = $ 400,000,
r = 3.5 %=0.035,
n = 12, ( 1 year = 12 months )
t = 20 years,
Thus, the amount would be,
![A=400000(1+(0.035)/(12))^(240)](https://img.qammunity.org/2020/formulas/mathematics/college/pnbsqwg76vboka8b7a2x0wb9kdkb5x28d8.png)
![=400000((12.035)/(12))^(240)](https://img.qammunity.org/2020/formulas/mathematics/college/q2xky87318nrybvoazyosweqf6kood7fri.png)
![=\$ 804680.813963](https://img.qammunity.org/2020/formulas/mathematics/college/ezhck14kml1juj3vc0n60flz8ehspes1y8.png)
![\approx \$ 804680.814](https://img.qammunity.org/2020/formulas/mathematics/college/g2c0bjft6f1qoaueg8aiabfg6gobgp875u.png)