Here we are given the formula for compound interest as :
![A=P(1+(r)/(n))^(nt)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/hn0qxctrr2hvd4ilxunbz6lfdd2lzo1t0v.png)
Here
A= Amount
P=Principal
r=rate of interest
n=number of times interest is compounded per year
t=time(years)
So we are given
P= $400
r=4% or 0.04
t= 11 years
n= 12
Plugging these values in the formula for compound interest we have,
![A=400(1+(0.04)/(12))^(12*11)](https://img.qammunity.org/2019/formulas/mathematics/middle-school/k6vw1e182jiveylakf9g6y67gr0u4d67b9.png)
A= $620.6286
Amount = $620.6
Answer: The final amount after 11 years will be $620.6 .